dephosphorylation is the removal of a phosphate ( po ₄ 3 − ) group from an organic compound by hydrolysis .

it is a reversible post-translational modification .

dephosphorylation and its counterpart , phosphorylation , activate and deactivate enzymes by detaching or attaching phosphoric esters and anhydrides .

a notable occurrence of dephosphorylation is the conversion of atp to adp and inorganic phosphate .

dephosphorylation employs a type of hydrolytic enzyme , or hydrolase , which cleave ester bonds .

the prominent hydrolase subclass used in dephosphorylation is phosphatase .

phosphatase removes phosphate groups by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl ( - oh ) group .

the reversible phosphorylation-dephosphorylation reaction occurs in every physiological process , making proper function of protein phosphases necessary for organism viability .

because protein dephosphorylation is a key process involved in cell signalling , protein phosphatases are implicated in conditions such as cardiac disease , diabetes , and alzheimer 's disease .

dephosphorylation

atp induces dephosphorylation of myosin light chain in endothelial cells . - pubmed - ncbi
dephosphorylation of thylakoid proteins increases compactness of thylakoid membranes from wild - type plants .
phosphorylation and dephosphorylation are not the only post - translational modifications that regulate the clock .
occupation of atp acceptor site by atp and its analogs resists t308 dephosphorylation in vitro .
phosphate analysis and dephosphorylation of modified tau associated with paired helical filaments . - pubmed - ncbi
dephosphorylation is the process by which phosphate groups are removed from a molecule by a phosphatase . removal of phosphate groups from a dna fragment can prevent ligation . learn more about dephosphorylation and phosphatases .
atp dephosphorylation can be either enhanced or inhibited by ph - controlled interaction with a dendrimer molecule .
phosphatases are hydrolases ; they use water to take away a phosphate from a substrate ( dephosphorylation ) .
figure 6 . 2 . figure 6 . 2 . the modification of proteins by phosphorylation and dephosphorylation .
human akt2 with r274h mutation decreased cell viability and failed to resist dephosphorylation in the presence of atp .
gaba ( a ) receptor dephosphorylation followed by internalization is coupled to neuronal death in in vitro ischemia .
the phosphorylation and dephosphorylation of glycogen / insulin controlling enzymes form part of a complex signaling cascade . what we want to highlight here is that in this instance is that the phosphorylation and dephosphorylation are directly linked .
correction : atp dephosphorylation can be either enhanced or inhibited by ph - controlled interaction with a dendrimer molecule .
) . these findings uncover a novel mechanism by which ceramide - induced dephosphorylation of bax increases its proapoptotic potency .
dephosphorylation targets bcl - 2 for ubiquitin - dependent degradation : a link between the apoptosome and the proteasome pathway .
protein dephosphorylation has been observed in neoplasms , malignant neoplasms , tissue adhesions , retinoblastoma , carcinoma . the study of protein dephosphorylation has been mentioned in research publications which can be found using our bioinformatics tool below . related pathways to protein dephosphorylation have been researched including cell cycle , localization , cell death , mitosis , cell proliferation . protein dephosphorylation products complement our catalog of research reagents including antibodies and elisa kits against mapk , akt1 , cdk1 , cdkn1a , dusp1 .
atp dephosphorylation can be either enhanced or inhibited by ph - controlled interaction with a dendrimer molecule . - pubmed - ncbi
) equivalent distribution for phosphatases . the data contains 43 dephosphorylation reactions , comprising 16 unique phosphatases and 32 unique targets .
role of protein phosphatase 1 in dephosphorylation of ebola virus vp30 protein and its targeting for the inhibition of viral transcription .
to determine the specificity of atp acceptor site occupancy for dephosphorylation resistance , we tested the effects of several other atp - derivatives on myrakt1 dephosphorylation . atp , atp - γs , and a - 443654 significantly reduced akt dephosphorylation in the presence of i - t15a pseudosubstrate peptide ( fig . 3 a ) . on the other hand , adp and adp - βs were markedly less effective in blocking dephosphorylation at both 10 min and 30 min incubation time points ( fig . 3 a ) .
) . dephosphorylation of psii was induced by incubation of the thylakoid suspension at 42°c for 40 min . the immunodetection analysis of thylakoid proteins with antiphosphothreonine antibodies confirmed dephosphorylation of the d1 , d2 , and cp43 proteins in the thylakoids treated at 42°c (
gaba ( a ) receptor dephosphorylation followed by internalization is coupled to neuronal death in in vitro ischemia . - pubmed - ncbi
the number of colonies that do not contain an insert seems high . how can i tell if the quick dephosphorylation kit worked ?
uses a signaling cascade of protein phosphorylation and dephosphorylation reactions to control its flagellar motors in response to environmental chemical changes ( fig .
) . these results indicate that the reduced d1 / d2 phosphorylation level in ws - 4 is not due to dephosphorylation reactions .
1 % sds lyses everything , including phosphatase enzymes . it is important not to use 10 % sds prior to dephosphorylation treatment .
the rapid dna dephos & ligation kit enables fast and efficient dephosphorylation and ligation of sticky - or blunt - end dna fragments .
proposed model of pp2a - induced bax dephosphorylation in regulating apoptosis . pp2a - induced bax dephosphorylation causes a conformational change in bax and facilitates bax translocation to mitochondria , insertion into mitochondrial membranes , and formation of oligomers , which lead to cyt c release and apoptosis . furthermore pp2a - induced bax dephosphorylation disrupts bcl2 / bax binding . this may prevent bcl2 from suppressing the proapoptotic function of bax .
iqbal k , zaidi t , bancher c , et al . alzheimer paired helical filaments . restoration of the biological activity by dephosphorylation .
synthetic polyammonium / polyamine receptors are known to enhance atp dephosphorylation in solution . atp interaction with a g - 3 poly ( ethylene imine ) dendrimer shows an unprecedented behaviour , the dendrimer catalyst being able to enhance or inhibit dephosphorylation of the nucleotide depending on the solution ph .
) . these findings indicate that ceramide - induced bax dephosphorylation may induce a conformational change in bax leading to activation of its proapoptotic function .
do you know of cases where dephosphorylation is atp dependent . i certainly don ' t . you can add that info in your question .
role of protein phosphatase 1 in dephosphorylation of ebola virus vp30 protein and its targeting for the inhibition of viral transcription . - pubmed - ncbi
what made you want to look up dephosphorylation ? please tell us where you read or heard it ( including the quote , if possible ) .
the quick dephosphorylation kit contains quick cip , a heat - labile version of calf intestinal alkaline phosphatase ( cip ) purified from a recombinant source .
ksiezak - reding h , liu wk , yen sh , et al . phosphate analysis and dephosphorylation of modified tau associated with paired helical filaments .
is the junctional uncoupling elicited in rat ventricular myocytes by some dephosphorylation treatments due to changes in the phosphorylation status . . . - pubmed - ncbi
) . molecules that bind akt , but fail to protect akt dephosphorylation will likely adopt conformation similar to adp . on the other hand , the dephosphorylation protective crystal structure of akt bound to a - 443654 ( pdb2jdr ) is nearly identical to the amp - pnp bound conformation ( pdb1o6k ) .
heat shock induces rapid dephosphorylation of tau in both female and male rats followed by hyperphosphorylation only in female rats : implications for alzheimer ' s disease .
liu f , iqbal k , grundke - iqbal i , et al . dephosphorylation of tau by protein phosphatase 5 : impairment in alzheimer ' s disease .
) . an alkali extraction experiment was used to test whether ceramide - induced bax dephosphorylation can promote bax insertion into mitochondrial membranes . a549 cells were treated with c
heat shock induces rapid dephosphorylation of tau in both female and male rats followed by hyperphosphorylation only in female rats : implications f . . . - pubmed - ncbi
adherent cells : this protocol is not recommended for adherent cells due to non - optimal lysing conditions . the ‘dephosphorylation of fixed protein on membrane’ protocol is recommended .
citation : martins bmc , swain ps ( 2013 ) ultrasensitivity in phosphorylation - dephosphorylation cycles with little substrate . plos comput biol 9 ( 8 ) : e1003175 . urltoken
a model of a phosphorylation - dephosphorylation cycle for an allosteric substrate with multiple phosphorylation sites has two “sink” states and multiple competitions between the modifying enzymes for the substrate .
wang j - z , gong c - x , zaidi t , et al . dephosphorylation of alzheimer paired helical filaments by protein phosphatase - 2a and - 2b .
) . these data suggest that ceramide - induced bax dephosphorylation can promote insertion of bax into mitochondrial membranes . to assess whether dephosphorylation affects the ability of membrane - inserted bax to form oligomers in the mitochondrial membrane , a cross - linking study using bis ( sulfosuccinimidyl ) suberate and disuccinimidyl suberate was carried out following treatment of cells with c
dephosphorylation is a key regulator of bk channel function in many systems including in the nervous system ( reinhart , chung , martin , brautigan , & levitan , 1991 ) .
rintamaki , e . , kettunen , r . , and aro , e . m . ( 1996 ) . differential d1 dephosphorylation in functional and photodamaged photosystem ii centers . dephosphorylation is a prerequisite for degradation of damaged d1 . j . biol . chem . 271 , 14870–14875 . doi : 10 . 1074 / jbc . 271 . 25 . 14870
the quick dephosphorylation kit contains quick cip , a heat - labile recombinant version of calf intestinal alkaline phosphatase ( cip ) purified from a recombinant source . quick cip nonspecifically catalyzes the dephosphorylation of 5´ and 3´ ends of dna and rna phosphomonoesters . it also hydrolyses ribo - and deoxyribonucleoside triphosphates ( ntps and dntps ) . quick cip is useful in many applications that require the dephosphorylation of dna or rna ends . in cloning , dephosphorylation prevents re - ligation of linearized plasmid dna . the enzyme can quickly dephosphorylate 5´ protruding , 5´ recessed , and blunt ends in just 10 minutes . quick cip may also be used to degrade unincorporated dntps in pcr reactions to prepare templates for dna sequencing or snp analysis .
c ) . furthermore , pretreatment with mkp antisense oligonucleotides completely prevented erk dephosphorylation after 6 h of tnf - α stimulation , whereas mkp sense oligonucleotides did not affect erk activity ( data not shown ) . this inhibition of erk dephosphorylation was associated with the complete inhibition of tnf - α - induced apoptosis of huvec ( p < 0 . 05 ; fig .
– the dissociation rate of the enzyme - substrate complexes – is much smaller than the other rates ) and a subsensitive minimum of 0 . purely distributive schemes of phosphorylation - dephosphorylation (
) created a chey mutant ( chey - n59r ) that exhibited normal phosphorylation , autodephosphorylation , and chez binding but was highly “resistant” to chez augmentation of its dephosphorylation rate ( fig .
we have 1750 products for the study of dephosphorylation that can be applied to western blot , flow cytometry , immunocytochemistry / immunofluorescence , immunohistochemistry from our catalog of antibodies and elisa kits .
) . thus , most likely , intrinsic binding of atp also shields phosphorylated mek and pkc from dephosphorylation by phosphatases . of note , we took account of and confirmed a previous report (
the dephosphorylation rate of p - lhcii at low light in vivo cannot be estimated with thr ( p ) antibody because of strong lhcii phosphorylation activity . however , the dephosphorylation rate of p - lhcii in vitro in phosphorylated thylakoids was very similar at both low and high light , the rates being very close to that estimated in vivo at high light ( table i ) .
liu f , zaidi t , grandke - iqbal i , et al . aberrant glycosylation modulates phosphorylation of tau by protein kinase a and dephosphorylation of tau by protein phosphatase 2a and 5 .
next we determined whether occupation of the atp acceptor site regulated t308 dephosphorylation in cell extracts . to this end , constitutively phosphorylated myrakt1 was expressed in hela cells followed by rapid dry - ice freezing / extraction . upon further incubation of cell extracts at 30 °c , myrakt1 was dephosphorylated within 15 min and both , calyculin and the a - 443654 akt inhibitor independently blocked t308 dephosphorylation ( fig . 2 a ) . however , unlike calyculin , a - 443654 inhibited akt1 dephosphorylation but not dephosphorylation of gsk - β , pras40 , or erk1 / 2 ( fig . 2 a , fig . s2 a ) . thus , in cell extracts devoid of kinase activity due to the presence of edta , a - 443654 specifically inhibited dephosphorylation of myrakt1 . this effect of a - 443654 extended to constitutive phosphorylated wt - akt in per - vanadate - treated hela cell extracts ( fig . s2 b ) . and in insulin - treated h9c2 cell extracts ( fig . s2 c ) .
phosphorylation adds a phosphate group to proteins ( e . g . enzymes ) to signal their activation or deactivation . dephosphorylation entails the removal of a phosphate group from a protein ( e . g . enzyme ) signaling its deactivation or activation . in the case of phosphorylation , the addition of a phosphate usually , signals activation while in dephosphorylation it usually is the opposite . the major difference between phosphorylation and dephosphorylation are the enzymes involved . both processes work on “as - needed” basis . they may not necessarily always talk to each other , but they do serve opposing roles which are sometimes mediated by other players . the processes of phosphorylation and dephosphorylation are complex and important processes governed by strong regulatory controls . phosphate donors play an important role , as they provide the basis of these two processes .
we next used pp2 , a selective inhibitor of the src family of tyrosine kinases , as a positive control to assess the relative magnitude of the dephosphorylation effect . when slices were exposed to 10 μ
the nature of chez has long been a mystery . is chez simply an allosteric effector that augments the rate of chey autodephosphorylation , or does chez catalyze a novel chey dephosphorylation reaction ? chez is known to bind tightly to phospho - chey and in this way might induce a conformational change that enhances the dephosphorylation reaction . however , the recently solved structure of a chez - chey cocrystal revealed that at least one chez residue , gln - 147 , plays a catalytic role in the dephosphorylation of phospho - chey ( 21 ) . thus , the chez - mediated reaction is distinctly different from chey autodephosphorylation .
so , what is the difference between phosphorylation and dephosphorylation ? this is the million dollar question . these two processes are not necessarily as a result of the other one . you will see below that while they often work hand in hand they do not necessarily follow each other closely , they simply each identify a need and then proceed to fill that need . in some cases , it may very well happen that the phosphorylation happens following dephosphorylation but is some cases their relationship is indirect ( see below ) . phosphorylation refers to an addition of a phosphate group while dephosphorylation refers to the removal of a phosphate group
szomolay b , shahrezaei v ( 2012 ) bell - shaped and ultrasensitive dose - response in phosphorylation - dephosphorylation cycles : the role of kinase - phosphatase complex formation . bmc syst biol 6 : 26 .
discovery of a chey residue specifically needed for chez - mediated dephosphorylation . green diamond , chey ; red square , chez . ( a ) summary of chey dephosphorylation reactions . chey autophosphorylates at aspartate - 57 . the other active - site residues needed for that reaction are also involved in autodephosphorylation . chez residue q147 plays an active role in accelerating the dephosphorylation of chey . the chey - n59r mutation has no effect on autodephosphorylation but disrupts chez - mediated dephosphorylation , even though n59 itself has no role in the chez - mediated reaction . ( b ) mechanism of the chey - n59r effect deduced by silversmith et al . ( 15 ) . the arginine side chain makes a salt bridge to the carboxyl group of chey - e89 , which prevents it from participating , as it normally does , in the chez - mediated reaction .
to study the activity of the psii core protein phosphatase , in vitro dephosphorylation experiments were carried out at 22°c and 44°c , the latter chosen since it is known that the phosphatase is activated by such elevated temperature [ 29 ] . western blots with anti - phosphothreonine antibodies of thylakoids at both temperatures indicated that d1 protein dephosphorylation proceeds with similar time course in ws - 4 and col - 0 , and is faster in l er - 0 ( figure 7c and d ) . it is not clear at present whether the faster dephosphorylation observed in l er - 0 has any physiological relevance since the steady state levels of psii phosphoproteins were found similar in l er - 0 and col - 0 ( figure 7a ) . these results indicate that the reduced d1 / d2 phosphorylation level in ws - 4 is not due to dephosphorylation reactions .
various stresses activate the c - jun n - terminal kinase ( jnk ) , which is involved in the regulation of many aspects of cellular physiology , including apoptosis . here we demonstrate that in contrast to uv irradiation , heat shock causes little or no stimulation of the jnk - activating kinase sek1 , while knocking out the sek1 gene completely blocks heat - induced jnk activation . therefore , we tested whether heat shock activates jnk via inhibition of jnk dephosphorylation . the rate of jnk dephosphorylation in unstimulated cells was high , and exposure to uv irradiation , osmotic shock , interleukin - 1 , or anisomycin did not affect this process . conversely , exposure of cells to heat shock and other protein - damaging conditions , including ethanol , arsenite , and oxidative stress , strongly reduced the rate of jnk dephosphorylation . under these conditions , we did not observe any effects on dephosphorylation of the homologous p38 kinase , suggesting that suppression of dephosphorylation is specific to jnk . together , these data indicate that activation of jnk by protein - damaging treatments is mediated primarily by inhibition of a jnk phosphatase ( s ) . elevation of cellular levels of the major heat shock protein hsp72 inhibited a repression of jnk dephosphorylation by these stressful treatments , which explains recent reports of the suppression of jnk activation by hsp72 .
2 . dephosphorylation of dna using shrimp alkaline phosphatase shrimp alkaline phosphatase , cat . no . p9088 is supplied as a solution in 50 % glycerol containing 25 mm tris - hcl , ph 7 . 6 , 1 mm mgcl 2 and 0 . 1 mm zncl 2 . dilutions can be prepared in 0 . 05 m tris - hcl , ph 8 . 5 containing 5 mm mgcl 2 . dephosphorylation should be carried out in 0 . 05 m tris - hcl , 5 mm mgcl 2 , ph 8 . 5 . heat inactivation : after the dephosphorylation reaction , the enzyme can then be inactivated by warming to 60 °c for 15 minutes .
our results suggested that dephosphorylation of ser87 plays a predominant role as a signal for ubiquitin - dependent degradation of bcl - 2 . to demonstrate directly that tnf - α indeed triggers dephosphorylation of ser87 , we transiently expressed myc - tagged bcl - 2 constructs in huvec . cells were lysed following treatment with or without tnf - α . to determine ser87 phosphorylation , immunoprecipitation was carried out with an anti - phosphoserine - specific antibody , and western blot analysis was performed with an anti - myc antibody . bcl - 2 degradation in consequence to dephosphorylation was prevented by using degradation - resistant , lysine - free bcl - 2 constructs . as shown in fig .
phospho - chey and phospho - cheb undergo rapid dephosphorylation , which enables the chemoreceptors to shift chey and cheb phosphorylation states on a short time scale by modulating the production of signaling phosphates by chea . both response regulators undergo self - catalyzed dephosphorylation , but phospho - cheb has a much shorter half - life than phospho - chey ( 17 ) . to compensate , another e . coli signaling component , chez , is specifically dedicated to accelerating chey dephosphorylation ( 6 ) . cells that lack chez are nonchemotactic and respond to stimuli with response latencies of seconds rather than milliseconds , demonstrating the critical importance of rapid phospho - chey turnover ( 8 , 13 ) .
to rule out that atp or a - 443654 directly inhibited pp2a catalytic activity , we determined the effects atp and a - 443654 on pp2a - dependent dephosphorylation of a target unrelated to akt , phospho - pras40 . under conditions identical to those used in the akt dephosphorylation assay , neither atp nor a - 443654 affected the ability of pp2a to dephosphorylate pras40 ( fig . 3 b ) . finally , to determine whether wt - akt similarly resisted pp2a - c dephoshorylation in vitro , we immunoprecipitated prephosphorylated ha - tagged or flag - tagged wt - akt1 from hela cells . fig . 3 c shows that both ha - tagged and flag - tagged phospho - wt - akt1 resisted pp2a - c dephosphorylation in the presence of atp or a - 443654 . collectively , these data suggest that atp inhibited akt1 dephosphorylation , not by inhibiting pp2a activity , but by binding to akt kinase .
laverne is a handy bioinformatics tool to help facilitate scientific exploration of related genes , diseases and pathways based on co - citations . explore more on dephosphorylation below ! for more information on how to use laverne , please read the
] . these are examples showing that inhibition of dysregulation of protein phosphorylation / dephosphorylation is a promising target to treat ad . further investigation of new compounds that can inhibit abnormal hyperphosphorylation of tau will likely provide new treatments for ad .
jeyaraman m , tanguy s , fandrich rr , lukas a , kardami e ( 2003 ) ischemia - induced dephosphorylation of cardiomyocyte connexin - 43 is reduced by okadaic acid and calyculin a but not fostriecin . mol cell biochem 242 : 129–134
a number of photosystem ii ( psii ) associated proteins , including core proteins d1 , d2 and cp43 , and several proteins of the lhcii complex , are phosphorylated by a thylakoid - bound , redox - regulated kinase ( s ) . we demonstrate here that the compound propyl gallate is an effective inhibitor of lhcii phosphorylation in vivo while having little effect on psii core protein phosphorylation . using this inhibitor , we demonstrate that lhcii dephosphorylation is insensitive to light in vivo . taken together with our previous conclusion ( elich et al . , embo j . 12 ( 1993 ) 4857–4862 ) that psii core protein dephosphorylation is light - stimulated , our data suggest the presence of multiple phosphatases responsible for thylakoid protein dephosphorylation in vivo .
rokka a , aro e - m , herrmann rg , andersson b , vener av ( 2000 ) dephosphorylation of photosystem ii reaction center proteins in plant photosynthetic membranes as an immediate response to abrupt elevation of temperature . plant physiol 123 : 1525–1536 .
duthe f , dupont e , verrecchia f , plaisance i , severs nj , sarrouilhe d , hervé jc ( 2000 ) dephosphorylation agents depress gap junctional communication between rat cardiac cells without modifying the connexin43 phosphorylation degree . gen physiol biophys 19 : 441–449
in cultured porcine aortic endothelial monolayers , the effect of atp on myosin light chain ( mlc ) phosphorylation , which controls the endothelial contractile machinery , was studied . atp ( 10 microm ) reduced mlc phosphorylation but increased cytosolic ca ( 2 + ) concentration ( [ ca ( 2 + ) ] ( i ) ) . inhibition of the atp - evoked [ ca ( 2 + ) ] ( i ) rise by xestospongin c ( 10 microm ) , an inhibitor of the inositol trisphosphate - dependent ca ( 2 + ) release from endoplasmic reticulum , did not affect the atp - induced dephosphorylation of mlc . mlc dephosphorylation was prevented in the presence of calyculin a ( 10 nm ) , an inhibitor of protein phosphatases pp - 1 and pp - 2a . thus atp activates mlc dephosphorylation in a ca ( 2 + ) - independent manner . in the presence of calyculin a , mlc phosphorylation was incremented after addition of atp , an effect that could be abolished when cells were loaded with the ca ( 2 + ) chelator 1 , 2 - bis ( 2 - aminophenoxy ) ethane - n , n , n ' , n ' - tetraacetic acid acetoxymethyl ester ( 10 microm ) . thus atp also activates a ca ( 2 + ) - dependent kinase acting on mlc . in summary , atp simultaneously stimulates a functional antagonism toward both phosphorylation and dephosphorylation of mlc in which the dephosphorylation prevails . in endothelial cells , atp is the first physiological mediator identified to activate mlc dephosphorylation by a ca ( 2 + ) - independent mechanism .
beardslee ma , lerner dl , tadros pn , laing jg , beyer ec , yamada ka , kleber ag , schuessler rb , saffitz je ( 2000 ) dephosphorylation and intracellular redistribution of ventricular connexin43 during electrical uncoupling induced by ischemia . circ res 87 : 656–662
—our data suggest that ceramide - stimulated bax dephosphorylation occurs in a mechanism involving activation of pp2a . to test whether dephosphorylation of bax affects its conformational change , an anti - 6a7 bax antibody that specifically measures the conformational change of bax was used . the monoclonal antibody 6a7 , raised against the peptide amino acids 13 - 19 in the n terminus of bax , is not able to bind the soluble form of bax in healthy cells but can recognize bax after the conformational change associated with membrane insertion occurs in apoptotic cells (
is protein dephosphorylation most commonly spontaneous ( without need of atp ) ? i came across some papers that mention it , as well as the opposite case ( atp - driven ) , but i can ' t figure out which is common or which is rare .
) determined the crystal structure of chey - n59r complexed with a stable phosphoryl group analog . in a tightly reasoned series of experiments , they showed that glu - 89 of chey , not asn - 59 , was critical to the chez - mediated dephosphorylation reaction . the chez resistance of chey - n59r proved to be due to formation of a salt bridge between the side chains of arg - 59 and glu - 89 that prevented the glu - 89 carboxyl group from participating in the chez - mediated dephosphorylation reaction ( fig .
what is phosphorylation ? phosphorylation refers to an addition of a phosphate group to a phosphate - accepting amino acid , such as serine and tyrosine . aphosphate group added onto a molecule ( usually a protein that is an enzyme ) activates it or , in some cases , deactivates it . what is dephosphorylation ? when this phosphate group “falls off , ” or is removed , once the protein has performed its function and needs to be deactivated ( in the case of phosphorylation - based activation ) . this is referred to as dephosphorylation .
in theory , the lack of p - lhcii accumulation at high light could be caused by an efficient lhcii dephosphorylation activity induced by high light . therefore , the in vivo dephosphorylation rate of p - lhcii was determined both in darkness and at high light . accumulation of p - lhcii was first induced by incubating the leaves at low light , and subsequently the loss of p - lhcii was recorded after shifting the leaves either to high light or to darkness . the rate constant for p - lhcii dephosphorylation was 2 times higher in high light ( 0 . 020 min −1 ) than in darkness ( 0 . 011 min −1 ) ( table i ) . nevertheless , even in high light , the half - life of p - lhcii was as long as 34 min ( table i ) .
. in endogenous conditions it is possible that non - distributive and distributive mechanisms coexist within the same phosphorylation - dephosphorylation cycle . some sites may be phosphorylated or dephosphorylated processively and others distributively , as has been suggested for the phosphorylation of the pho4 transcription factor in budding yeast
binding to d3 - phosphorylated phosphoinositide lipids anchors the akt1 protein kinase at cell membranes , enables activation loop phosphorylation ( t308 in akt1 ) , and induces akt kinase activity . similarly , targeting akt1 to the cell membrane with a fusion protein consisting of akt1 and myristoylation signal ( myrakt1 ) was associated with “constitutive” t308 phosphorylation in h9c2 myoblasts as it occurred in culture medium lacking exogenous growth factors ( fig . 1 a ) . adding an allosteric inhibitor of the akt kinase ( inhibitor viii ) to these cells led to myrakt1 dephosphorylation ( > 90 % ) within 30 min and dephosphorylation was inhibited by phosphatase inhibitors , calyculin or okadaic acid ( fig . 1 b ) . furthermore , the atp - competitive akt inhibitor , a - 443654 , prevented inhibitor - viii - induced akt dephosphorylation even more effectively than the phosphatase inhibitors .
to determine whether a - 443654 also inhibited dephosphorylation of wild - type ( wt ) - akt1 , h9c2 cells were stimulated with insulin for 20 min to induce endogenous akt phosphorylation . to effect akt dephosphorylation , cells were then incubated in growth factor - free medium with and without the pdk1 inhibitor , ucn01 , or the pi - 3 kinase inhibitor , wortmannin . under these conditions , a - 443654 delayed akt dephoshorylation at both t308 and s473 sites ( fig . 1 c ) . we further observed that , in growth factor - starved conditions , a - 443654 treatment alone only weakly induced akt1 phosphorylation , yet a - 443654 potently synergized with insulin to induce akt1 hyperphosphorylation at t308 ( fig . s1 a ) . these results are consistent with the hypothesis that a - 443654 induces akt hyperphosphorylation by inhibiting akt dephosphorylation .
dephosphorylation is a common step in traditional cloning workflows to ensure that the vector does not re - circularize during ligation . if a vector is linearized by a single restriction enzyme , or has been cut with two enzymes with compatible ends , use of a phosphatase , such as the
many molecules are energy donors that serve to supply the phosphate group ; these include adenosine triphosphate ( atp , also famous in photosynthesis ) and guanosine triphosphate ( gtp ) . phosphorylation prepares molecules for the tasks they need to perform . this phosphate sticks around as long as the protein needs it and then is lost or dropped . there are different types of phosphorylation . in this article , we will look at a few examples of phosphorylation ( and dephosphorylation ) , and go through the importance of phosphorylation and dephosphorylation as well as how they differ from each other .
the present study reports for the first time the use of a thiol - functionalized graphene oxide nanocatalyst with impressive activity ( > 10 5 - fold ) in dephosphorylation reactions . the innovative and recyclable nanocatalyst has potential in designing artificial enzymes with targeted multifunctionalities and in detoxification of organophosphorus agents .
changes in protein phosphorylation represent a mechanism that is frequently employed by cells to regulate transcription factor activity . in response to alterations in the extracellular environment , signal transduction pathways target transcription factors , transcriptional coregulators and chromatin - modifying factors , leading to their phosphorylation by protein kinases or dephosphorylation by protein phosphatases . these modifications either positively or negatively regulate transcription factor activity to facilitate a program of gene expression that results in appropriate changes in cell behavior . protein phosphorylation and dephosphorylation can directly regulate distinct aspects of transcription factor function , including cellular localization , protein stability , protein - protein interactions and dna binding . the phosphorylation - dependent modulation of the activities of transcriptional coregulators and chromatin - modifying factors can also control transcription factor activity . here we review recent studies that have led to a better understanding of the mechanisms by which protein phosphorylation and dephosphorylation governs transcription factor function .
activating mutations in fibroblast growth factor receptor 3 ( fgfr3 ) and inactivating mutations of guanylyl cyclase - b ( gc - b , also called nprb or npr2 ) cause dwarfism . fgf exposure inhibits gc - b activity in a chondrocyte cell line , but the mechanism of the inactivation is not known . here , we report that fgf exposure causes dephosphorylation of gc - b in rat chondrosarcoma cells , which correlates with a rapid , potent and reversible inhibition of c - type natriuretic peptide - dependent activation of gc - b . cells expressing a phosphomimetic mutant of gc - b that cannot be inactivated by dephosphorylation because it contains glutamate substitutions for all known phosphorylation sites showed no decrease in gc - b activity in response to fgf . we conclude that fgf rapidly inactivates gc - b by a reversible dephosphorylation mechanism , which may contribute to the signaling network by which activated fgfr3 causes dwarfism .
protein phosphatases have also found a role in this pathway rich in phosphorylation events . protein phosphatase2a ( pp2a ) holoenzymes have been shown to participate in at least two steps . on the one hand , the activity and / or localization of pp2a presumably leads to the dephosphorylation of activated bri1 , accelerating its turnover and shutting off the response ( wu et al . , 2011 ) . on the other hand , regulatory subunits of pp2a associate with bzr1 ; upon inactivation of bin2 , dephosphorylation of bzr1 allows its rapid accumulation in the nucleus and the consequent transcriptional effects ( tang et al . , 2011 ) .
rokka , a . , aro , e . - m . , herrmann , r . g . , andersson , b . , and vener , a . v . ( 2000 ) . dephosphorylation of photosystem ii reaction center proteins in plant photosynthetic membranes as an immediate response to abrupt elevation of temperature .
these different forms of phosphorylation that take place ( mostly during photosynthesis ) happen in response to the dephosphorylation of numerous atp molecules as they serve their many important functions . this all happens in a sort of divide and concur fashion , in a hurry to ensure that atp stocks are restored as speedily as possible .
studies during the last two decades have provided new insights into the molecular mechanism of alzheimer ' s disease ( ad ) . one of the milestone findings in ad research was the demonstration that neurofibrillary degeneration characterized by tau pathology is central to the pathogenesis of ad and other tauopathies and that abnormal hyperphosphorylation of tau is pivotal to neurofibrillary degeneration . this article reviews the recent research advances in tau pathology and the underlying dysregulation of the protein phosphorylation / dephosphorylation system . an updated model of the mechanism of neurofibrillary degeneration is also presented , and a promising therapeutic target to treat ad by correcting dysregulation of protein phosphorylation / dephosphorylation is discussed .
a443654 or atp binding inhibits akt dephosphorylation . ( a ) a443654 inhibits myrakt1 dephosphorylation in cell extracts . myrakt1 expressing hela cells were flash - frozen and extracted in ice . aliquots of cell extracts were treated with a443654 or calyculin on ice before incubation at 30 °c for 15 min . after incubation , protein extracts were subjected to immunoblot analysis using antibodies detecting phosphorylated akt ( t308 ) , gsk3β ( s9 ) , and pras40 ( t246 ) and gapdh . ( b ) a443654 inhibits recombinant pp2a - mediated akt dephosphorylation . immunoprecipitated myrakt1 was incubated with recombinant pp2a ( 40 ng pp2a - c ) for 30 min , 30 °c in the presence of a443654 ( 2–20 um ) . images show myrakt1 t308 phosphorylation , ha - tagged myrakt1 and pp2a - c expression . graph shows the percentage pt308 dephosphorylation . * p < 0 . 001 for pp2a vs . pp2a + a44 at 30 min . ( c ) atp inhibits recombinant pp2a - mediated akt dephosphorylation in the presence of akt - specific pseudosubstrate peptide ( i - t15a ) . immunoprecipitated myrakt1 was incubated with recombinant pp2a for 30 min , 30 °c in a buffer containing 5 mm mgcl2 , 400 um sonicated lipid micelles , 25 um high affinity akt pseudosubstrate inhibitor ( i - t15a ) and increasing concentrations of atp ( 0 , 20 um or 100 um ) as indicated . immunoblot images show myrakt1 t308 and s473 phosphorylation , ha - tagged myrakt1 and pp2a - c expression . graph shows the percentage pt308 dephosphorylation in the presence pp2a alone ( n = 11 ) , pp2a with 100 um atp ( n = 8 ) , with 25 um i - t15a peptide ( n = 3 ) or both ( n = 7 ) . * p < 0 . 001 vs . pp2a , # p < 0 . 05 vs . pp2a / atp , ^ p < 0 . 05 vs . pp2a / i - 15a ( nonparametric anova , kruskal - wallis ) .
to maximally activate endogenous akt , h9c2 cells were serum - starved for 4 h before stimulating with 1 ug / ml insulin for 20 min . to initiate dephosphorylation , insulin medium was replaced with serum - free medium in the presence of indicated inhibitors . after 10 min of incubation , cells were harvested for immunoblotting analysis .
an additional issue of significant import is which tyrosine residue ( s ) on the nmda receptor subunits is / are responsible for the observed change in phosphorylation . there are many tyrosine residues on the nr2 subunits that could be subject to phosphorylation and dephosphorylation . moreover , both nr2a and nr2b subunits are known to be substrates of fyn kinase (
here , we describe a molecular mechanism regulating the phosphorylation state of akt kinases that depend on subcellular location and on occupancy of the atp binding pocket . specifically , we demonstrate that recruitment of akt1 to the plasma membrane confers resistance to dephosphorylation of pt308 and this resistance further depends on atp acceptor site occupancy by atp or atp - competitive inhibitors . in vitro , binding of either atp or atp - competitive inhibitors rendered akt1 phospho - t308 highly resistant to dephosphorylation by the pp2a phosphatase . we propose that atp occupancy facilitates intramolecular interactions of phosphorylated t308 with two residues in the akt1 catalytic cleft ( r273 , h194 ) that restrict phosphatase access . this mechanism provides an explanation for akt hyperphosphorylation induced by atp - competitive but not allosteric akt inhibitors . disrupting these interactions by mutation obviates phosphatase resistance of pt308 and enables rapid dephosphorylation . mutation of the homologous site in akt2 ( r274h ) , known to cause autosomal - dominant insulin resistance in humans ( 4 ) , also obviates atp - induced phosphatase resistance at the akt2 t309 site .
phosphorylation state of cellular proteins reflects the balance between the activities of protein kinases and phosphoprotein phosphatases . the increase in cellular protein phosphorylation in response to stimuli can be achieved by either activating protein kinases and / or promoting the turnover of the protein phosphatases . this review will summarize current knowledge of the control of phosphorylation and dephosphorylation of protein in cells .
well of course why not . look at atp , which is not a stable molecule , because it can spontaneously dephosphorylate . whether a phosphate group can be spontaneously hydrolysed depends on the nature of the molecule it is a part of . are you asking about protein phosphorylations ? in almost all cases that i know of , dephosphorylation in not atp dependent .
this protein dephosphorylation method uses a two - step approach to focus on specificity and potency . the first treatment is done with a lambda phosphatase to specifically target phosphate groups from threonine , serine , and tyrosine amino acids for dephosphorylation . most phosphatases only dephosphorylate serine and threonine amino acids . if you are testing the phosphospecificity of a tyrosine phosphospecific antibody , lambda phosphatase is essential . the second dephosphorylation treatment is done with an alkaline phosphatase , a significantly more potent enzyme than lambda phosphatase . the alkaline phosphatase only dephosphorylates phosphate groups from threonine and serine amino acids , and therefore is not intended to be utilized alone to determine the phosphospecificity of tyrosine phosphospecific antibodies . when using both lambda and alkaline phosphatases in conjunction with each other , it is best to separate the treatments so the alkaline phosphatase doesn’t inhibit the activity of the lambda phosphatase . there are a variety of phosphatases one may use to dephosphorylate proteins ; the ones listed in this protocol are recommended examples . the end user is highly encouraged to optimize their chosen phosphatase ( s ) before determining phosphospecificity of an antibody .
dephosphorylation of plk1 following mitotic dna damage is independent of p53 and atm . a . dephosphorylation of plk1 is p53 independent . cells were synchronized with nocodazole and treated with 0 . 5 μmol / l adriamycin for 1 hour , replated with fresh media containing nocodazole , and harvested at the indicated times for plk1 lysate immunoblot analysis . top panel , ca46 cells ( mutant p53 ) . bottom panel , wmn cells ( wild - type p53 ) . b . caffeine does not affect dna damage–induced plk1 dephosphorylation . mitotic ca46 cells were mock treated or pretreated with 2 . 5 mmol / l caffeine for 1 hour , after which 0 . 5 μmol / l adriamycin was added to medium for 1 hour . cells were washed and cultured in fresh media containing nocodazole without ( top panel ) or with caffeine ( bottom panel ) and harvested at the indicated times for lysate plk1 immunoblot . c . mitotic dephosphorylation of plk1 is independent of atm . nocodazole - arrested atm mutant gm08436a ( bottom panel ) , and a normal control cell line , gm09622 ( top panel ) , were treated with 0 . 5 μmol / l adriamycin for 1 hour , washed , and re - plated with media containing nocodazole . cells were harvested for lysate plk1 immunoblot analysis at the indicated times . experiments were conducted at least three times for a and b with similar results . experiments were conducted three times in two atm mutant cell lines and two normal control cell lines with similar results .
it is commonly assumed that a simple phosphorylation - dephosphorylation cycle cannot generate ultrasensitivity if the enzymes are not saturated [ 44 ] . our model shows that this assumption is not true if biochemistry is modelled more closely to include docking sites for the enzymes on the substrate . given that there is little evidence for selection on the ratio of the in vivo concentration of kinases to their substrates ( as we have shown here ) , we expect that our mechanism may be common . phosphorylation - dephosphorylation cycles require energy to operate , but our results emphasize again that “futile” cycles need not be expending energy needlessly but use that energy to generate ultrasensitivity , thus laying the foundation for sophisticated cellular responses such as irreversible switching and oscillations [ 4 ] .
cellular decision - making is driven by dynamic behaviours , such as the preparations for sunrise enabled by circadian rhythms and the choice of cell fates enabled by positive feedback . such behaviours are often built upon ultrasensitive responses where a linear change in input generates a sigmoidal change in output . phosphorylation - dephosphorylation cycles are one means to generate ultrasensitivity . using bioinformatics , we show that
the file biogrid - organism - saccharomyces _ cerevisiae - 3 . 1 . 87 . tab2 , which lists annotated protein - protein interactions in yeast , is available from biogrid ( urltoken ) [ 18 ] . we wrote a script to extract the phosphorylation and dephosphorylation interactions and combined the resulting list with the protein expression data of ghaemmaghammi et al . [ 19 ] .
plants . specific dephosphorylation of the d1 , d2 , and cp43 proteins induced by a heat shock treatment resulted in a faster gravity - driven sedimentation of the dephosphorylated thylakoids compared with the phosphorylated membranes . the identical heat shock treatment of thylakoids in the presence of phosphatase inhibitors prevented both dephosphoryation of thylakoid proteins and the increase in the density / compactness of the thylakoid membranes (
digested dna typically possesses a 5’ phosphate group that is required for ligation . in order to prevent self - ligation , the 5′ phosphate can be removed prior to ligation . dephosphorylation of the 5’ end prohibits self - ligation , enabling the researcher to manipulate the dna as desired before re - ligating . generally , it is a good idea to dephosphorylate the linearized vector to facilitate ligation of recombinant dna molecules . in fact , vector self - ligation increases the background activity of the cloning process . dephosphorylation can be accomplished using any of a number of phosphatases , including shrimp alkaline phosphatase ( rsap ) ( neb # m0371 ) , calf intestinal alkaline phosphatase ( cip ) ( neb # m0290 ) and antarctic phosphatase ( neb # m0289 ) .
21 , 404–408 ) . inclusion of bpv ( phen ) , a potent phosphotyrosine phosphatase inhibitor , in the recording chamber prior to and during ethanol exposure significantly reduced the inhibitory effect of ethanol on nmdar field excitatory postsynaptic potentials . taken together , these data suggest that phosphatase - mediated dephosphorylation of nmdar subunits may play an important role in mediating the inhibitory effects of ethanol on the
the most important free - energy molecule in the body is atp . atp is a useful free - energy currency because it can lose a phosphate group in a very spontaneous reaction ; i . e . , the dephosphorylation reaction releases a large amount of free energy . the dephosphorylation reaction of atp is often coupled with nonspontaneous reactions to drive them forward . to produce atp , another set of coupled reactions , known as oxidative phosphorylation , is used . oxidative phosphorylation consists of two major components : ( 1 ) the oxidation of molecules generated during the breakdown of glucose , which releases energy that causes a proton gradient to build up across a membrane , and ( 2 ) the phosphorylation of adp to make atp , using energy from the proton gradient .
) . we obtain 2850 phosphorylation reactions , comprising 98 unique kinases and 1136 unique substrates and 43 dephosphorylation reactions involving 16 unique phosphatases and 32 unique substrates . the data for phosphatases is scarce and thus not as informative , and so we focus on kinases . the distribution of ratios for kinases is unimodal , centred on a 1∶1 kinase to substrate ratio , with a minimum of
our data strongly suggest that pp2a can function as a physiologic bcl2 phosphatase to dephosphorylate bcl2 and regulate its association with p53 . to test whether pp2a is required for bcl2 dephosphorylation , bcl2 - expressing h7 cells were transfected with pp2a / c sirna to silence this phosphatase . results show that the pp2a / c sirna efficiently and specifically reduces pp2a / c expression by more than 90 % , whereas control sirna has no effect ( figure 5 a ) . importantly , the specific silencing of pp2a / c expression results in both enhanced bcl2 phosphorylation and inhibition of cisplatin - stimulated bcl2 / p53 binding in association with prolonged cell survival ( figure 5 ) . these findings suggest that pp2a may be required for dephosphorylation of bcl2 and facilitation or enhancement of p53 binding .
( purely distributive case ) . section 3 compares a model of phosphorylation - dephosphorylation cycles , which expends energy and hence has irreversible catalytic reactions , with a monod - wyman - changeux model , which does not expend energy and has reversible catalytic reactions . we show that the monod - wyman - changeux model is not ultrasensitive in response to changes in the concentrations of the enzymes .
if ethanol affects on nmdar function are indeed due to enhanced dephosphorylation of the receptor , we should be able to reduce ethanol ' s effect by blocking tyrosine phosphatase activity . to test this possibility , we examined the effect of ethanol on nmdar activity in the presence of the tyrosine phosphatase inhibitor bpv ( phen ) . pharmacologically isolated nmdar fepsps were recorded in area ca1 of hippocampal slices ( fig .
the present study sheds light on a unique molecular mechanism regulating phosphorylation states of akt1 and akt2 through binding of either atp or atp - competitive antagonists . the most salient findings of this study can be summarized as follows : ( i ) binding of atp or atp - competitive antagonists to akt1 restrained pp2a - mediated akt1 dephosphorylation ; and ( ii ) these effects were contingent on intramolecular interactions of phosphorylated t308 with h194 and r273 residues in the catalytic cleft of akt1 ; ( iii ) steady - state akt2 phosphorylation is similarly regulated by intramolecular interactions between t309 and r274 . the interactions between phosphorylated t308 and residues in the catalytic cleft of akt1 may restrict access of phosphatases to phosphorylated t308 , thus providing a “molecular cage” to shield phosphorylated t308 from dephosphorylation ( schematically depicted in fig . 6 a ) .
protein phosphatases reverse the effects of kinases through catalyzing the removal of phosphoryl groups from the proteins . the discussion around phosphorylation and dephosphorylation may lead to the assumption that these two processes are the reverse of each other . do not fall into this trap ; this is not true . deactivation of proteins can only be guided with the aid of phosphatases , while activation is through the aid of kinases ( amongst other things ) . so , while they are antagonistic , they are not necessarily undoing the other one’s job . strictly speaking , both processes are irreversible under natural physiological conditions . the rate of dephosphorylation and phosphorylation depend on enzymes and not each other . in other words , whether there are a hundred phosphorylated molecules or zero matters very little if the enzymes are not available or able to perform their function .
depletion of pp2a / c by rnai enhances bax phosphorylation in association with suppression of apoptosis —our data strongly suggest that pp2a functions as physiological bax phosphatase to dephosphorylate bax . to test whether pp2a is essential for bax dephosphorylation , a549 cells were transfected with pp2a / c sirna as described under “experimental procedures . ” results showed that the pp2a / c sirna efficiently and specifically reduced pp2a / c expression in a549 cells , whereas control sirna had no effect ( fig . 5 a ) . importantly specific disruption of pp2a / c expression by rnai not only resulted in bax phosphorylation but also further enhanced nicotine - stimulated bax phosphorylation in association with prolonged cell survival following treatment of cells with cisplatin ( fig . 5 ) . these findings suggest that pp2a may be required for dephosphorylation of bax to activate its proapoptotic activity .
to date , in vitro work on the e . coli signaling system has provided tantalizing hints that chez activity might be under stimulus control ( 20 ) , but the field still awaits an experimental slam dunk that resolves the issue . better understanding of the chez - mediated dephosphorylation reaction , including the role played by its chey substrate , may provide useful clues to the molecular nature of that elusive control mechanism .
analysis of the three - dimensional structures of akt bound to either atp or a - 443654 ( 18 , 19 ) suggested the possibility that the phosphorylated t308 interacts with h194 and r273 of the nucleotide - binding pocket ( fig . 4 a , fig . s3 b ) and that these intramolecular , atp binding - dependent interactions could shield pt308 from phosphatase attack . to test this hypothesis , we mutated either h194 or r273 in myrakt1 to alanine . cells expressing these mutants revealed markedly reduced steady - state t308 phosphorylation levels whereas inhibiting cellular phosphatases with calyculin restored high levels of t308 and s473 phosphorylation to the h194a and r273a mutants ( fig . 4 b ) . these results are consistent with the notion that these mutations primarily enhanced akt dephosphorylation . next , we isolated the r273a mutant protein by immunprecipitation and found that when myrakt1 or wt - akt1 r273 sites were mutated to alanine , neither atp nor nonhydrolyzable atp - γs were able to inhibit t308 dephosphorylation ( fig . 4 c ) . finally , mutating either h194 or r273 was sufficient to abolish atp - mediated dephosphorylation resistance ( fig . 4 d ) . these results support the hypothesis that molecular interactions of pt308 with h194 and r273 restrain pp2a access to this residue .