bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laforin is required for the functional activation of malin in endoplasmic reticulum stress resistance in neuronal cells
Authors: Zeng Li , Wang Yin , Baba Otto , Zheng Pan , Liu Yang , Liu Yan 
Published: May 2012

Mutations in either EPM2A, the gene encoding a dual‐specificity phosphatase named laforin, or NHLRC1, the gene encoding an E3 ubiquitin ligase named malin, cause Lafora disease in humans. Lafora disease is a fatal neurological disorder characterized by progressive myoclonus epilepsy, severe neurological deterioration and accumulation of poorly branched glycogen inclusions, called Lafora bodies or polyglucosan bodies, within the cell cytoplasm. The molecular mechanism underlying the neuropathogenesis of Lafora disease remains unknown. Here, we present data demonstrating that in the cells expressing low levels of laforin protein, overexpressed malin and its Lafora disease‐causing missense mutants are stably polyubiquitinated. Malin and malin mutants form ubiquitin‐positive aggregates in or around the nuclei of the cells in which they are expressed. Neither wild‐type malin nor its mutants elicit endoplasmic reticulum stress, although the mutants exaggerate the response to endoplasmic reticulum stress. Overexpressed laforin impairs the polyubiquitination of malin while it recruits malin to polyglucosan bodies. The recruitment and activities of laforin and malin are both required for the polyglucosan body disruption. Consistently, targeted deletion of laforin in brain cells from Epm2a knockout mice increases polyubiquitinated proteins. Knockdown of Epm2a or Nhlrc1 in neuronal Neuro2a cells shows that they cooperate to allow cells to resist ER stress and apoptosis. These results reveal that a functional laforin–malin complex plays a critical role in disrupting Lafora bodies and relieving ER stress, implying that a causative pathogenic mechanism underlies their deficiency in Lafora disease.Structured digital abstract
Malin
physically interacts;with Laforin and GS1 by pull down (View interaction)
GS1
and Laforin colocalize by fluorescence microscopy (View interaction)
Laforin
physically interacts with Malin by anti tag coimmunoprecipitation (View Interaction: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
Unraveling the thread of nature’s tapestry: the genetics of diversity and convergence in animal pigmentation
Authors: Kronforst Marcus R. , Barsh Gregory S. , Kopp Artyom , Mallet James , Monteiro Antónia , Mullen Sean P. , Protas Meredith , Rosenblum Erica B. , Schneider Christopher J. , Hoekstra Hopi E. 
Published: May 2012

SummaryAnimals display incredibly diverse color patterns yet little is known about the underlying genetic basis of these phenotypes. However, emerging results are reshaping our view of how the process of phenotypic evolution occurs. Here, we outline recent research from three particularly active areas of investigation: melanin pigmentation in Drosophila, wing patterning in butterflies, and pigment variation in lizards. For each system, we highlight (i) the function and evolution of color variation, (ii) various approaches that have been used to explore the genetic basis of pigment variation, and (iii) conclusions regarding the genetic basis of convergent evolution which have emerged from comparative analyses. Results from these studies indicate that natural variation in pigmentation is a particularly powerful tool to examine the molecular basis of evolution, especially with regard to convergent or parallel evolution. Comparison of these systems also reveals that the molecular basis of convergent evolution is heterogeneous, sometimes involving conserved mechanisms and sometimes not. In the near future, additional work in other emerging systems will substantially expand the scope of available comparisons.
Specifying protein kinase C functions in melanoma
Authors: Denning Mitchell F. 
Published: May 2012

SummaryThe protein kinase C (PKC) family of serine/threonine protein kinases is a heterogeneous group of enzymes receiving and integrating signals involved in both normal melanocyte biology and melanoma pathology. Alterations in PKC enzyme expression and activation contribute to the malignant phenotype of melanoma in both oncogenic and tumor suppressive roles. Delineating the diverse and often context‐dependent functions of PKC enzymes in melanocyte/melanoma biology is key to capitalize on these kinases as drug targets. This review summarizes several of the diverse functions of PKC in melanocyte and melanoma biology with a focus on PKC enzyme regulation and function.
A comparative analysis of the carbon intensity of biofuels caused by land use changes
Authors: Njakou Djomo Sylvestre , Ceulemans Reinhart 
Published: May 2012

AbstractWorldwide land is a limited resource and its use for the production of biofuels and other agricultural products can impact greenhouse gas emissions (GHG). Several models and approaches have been used to assess the direct (dLUC) and indirect land use change (iLUC) carbon intensity – i.e. the amount of CO2 emitted per unit of biofuel produced – of biofuels, but their outcomes diverge significantly. This analysis of 15 studies published between 2008 and 2010 (i) summarized and compared models and approaches used to estimate the dLUC and iLUC carbon intensities of biofuels, and (ii) assessed the mechanisms that led to the variation in the outcomes. The data show that the dLUC carbon intensity ranged from −52 to 34 g CO2 MJ−1, whereas the iLUC ranged from 0 to 327 g CO2 MJ−1 for bioethanol depending on the feedstock, on the type of land used or displaced and on the amortization period. The total LUC carbon intensity of bioethanol was found to be −29% to 384% of that of gasoline. This means that in some cases, LUC could potentially alter the GHG benefits of biofuels. Standardizing assumptions, carbon stock changes and methodologies for estimating the dLUC and iLUC carbon intensity will ensure more consistency and meaningful comparisons across studies in the future. This might then enable policy makers to make better justified judgments on the sustainability of biofuels.
Gastric emptying, intestinal absorption of electrolytes and exercise performance in electrolyte‐supplemented horses
Authors: Lindinger Michael I. , Ecker Gayle L. 
Published: May 2012

New Findings
What is the central question of this study?The study addresses whether electrolyte supplementation of horses one hour prior to exercise improves hydration and exercise performance.
What is the main findings and its importance?We used radiotracer methodologies to identify that 3L was the minimum amount of electrolyte supplement required to maintain hydration and replace plasma electrolytes lost by sweating. By maintaining hydration and plasma electrolyte concentrations sub‐maximal exercise duration was extended.
Horses lose considerably more electrolytes through sweating during prolonged exercise than can be readily replaced through feeds. The present study tested an oral electrolyte supplement (ES) designed to replace sweat electrolyte losses. We measured gastric emptying of 3 litres of ES (using gamma imaging of 99Tc‐sulfide colloid), the absorption of Na+ and K+ from the gastrointestinal tract using 24Na+ and 42K+, and the distribution of these ions in the body by measuring radioactivity within plasma and sweat during exercise. Three litres of ES emptied from the stomach as fast as water, with a half‐time of 47 min, and appeared in plasma by 10 min after administration (n= 4 horses). Peak values of plasma 24Na+ and 42K+ radioactivity occurred at 20–40 min, and a more rapid disappearance of K+ radioactivity from plasma was indicative of movement of K+ into cells (n= 3 horses). In a randomized crossover experiment (n= 4 horses), 1 h after administration of placebo (water), 1 or 3 litres of ES containing 24Na+, horses exercised on a treadmill at 30% of peak oxygen uptake until voluntary fatigue. The 24Na+ appeared in sweat at 10 min of exercise, and when horses received 3 litres of ES the duration to voluntary fatigue was increased in all horses by 33 ± 10%. It is concluded that an oral ES designed to replace sweat ion losses was rapidly emptied from the gastrointestinal tract, rapidly absorbed in the upper intestinal tract and rapidly distributed within the body. The ES clearly served as a reservoir to replace sweat ion losses during exercise, and administration of ES prior to exercise resulted in increased duration of submaximal exercise.
Noxious somatic stimuli diminish respiratory–sympathetic coupling by selective resetting of the respiratory rhythm in anaesthetized rats
Authors: Korim Willian S. , Egwuenu Eyitemi , Fong Angelina Y. , McMullan Simon , Cravo Sergio L. , Pilowsky Paul M. 
Published: May 2012

Noxious somatic stimulation evokes respiratory and autonomic responses. The mechanisms underlying the responses and the manner in which they are co‐ordinated are still unclear. The effects of activation of somatic nociceptive fibres on lumbar sympathetic nerve activity at slow (2–10 Hz) and fast frequency bands (100–1000 Hz) and the effects on respiratory–sympathetic coupling are unknown. In anaesthetized, artificially ventilated Sprague–Dawley rats under neuromuscular blockade, ensemble averaging of sympathetic activity following high‐intensity single‐pulse stimulation of the sciatic nerve revealed two peaks (∼140 and ∼250 ms) that were present at similar latencies whether or not slow or fast band filtering was used. Additionally, in the slow band of both lumbar and splanchnic sympathetic nerve activity, a third peak with a very slow latency (∼650 ms) was apparent. In the respiratory system, activation of the sciatic nerve decreased the expiratory period when the stimulus occurred during the first half of expiration, but increased the expiratory period if the stimulus was delivered in the second half of the expiratory phase. The phase shifting of the respiratory cycle also impaired the respiratory–sympathetic coupling in both splanchnic and lumbar sympathetic nerve activity in the subsequent respiratory cycle. The findings suggest that noxious somatosympathetic responses reduce the co‐ordination between respiration and perfusion by resetting the respiratory pattern generator.
Diversity of Gene Cassette Promoters in Class 1 Integrons from Wastewater Environments
Authors: Moura Alexandra , Jové Thomas , Ploy Marie-Cécile , Henriques Isabel , Correia António 
Published: May 2012

ABSTRACT
The diversity of gene cassette promoters in class 1 integrons was investigated in 47 strains isolated from wastewaters. The weak PcW and PcH1 variants predominated, suggesting that, similar to clinical environments, high rates of gene cassette recombination, rather than high expression of gene cassettes, have been preferentially selected in wastewaters.
Quantitative Estimation of the Viability of Toxoplasma gondii Oocysts in Soil
Authors: Lélu Maud , Villena Isabelle , Dardé Marie-Laure , Aubert Dominique , Geers Régine , Dupuis Emilie , Marnef Francine , Poulle Marie-Lazarine , Gotteland Cécile , Dumètre Aurélien , Gilot-Fromont Emmanuelle 
Published: May 2012

ABSTRACT

Toxoplasma gondii
oocysts spread in the environment are an important source of toxoplasmosis for humans and animal species. Although the life expectancy of oocysts has been studied through the infectivity of inoculated soil samples, the survival dynamics of oocysts in the environment are poorly documented. The aim of this study was to quantify oocyst viability in soil over time under two rain conditions. Oocysts were placed in 54 sentinel chambers containing soil and 18 sealed water tubes, all settled in two containers filled with soil. Containers were watered to simulate rain levels of arid and wet climates and kept at stable temperature for 21.5 months. At nine sampling dates during this period, we sampled six chambers and two water tubes. Three methods were used to measure oocyst viability: microscopic counting, quantitative PCR (qPCR), and mouse inoculation. In parallel, oocysts were kept refrigerated during the same period to analyze their detectability over time. Microscopic counting, qPCR, and mouse inoculation all showed decreasing values over time and highly significant differences between the decreases under dry and damp conditions. The proportion of oocysts surviving after 100 days was estimated to be 7.4% (95% confidence interval [95% CI] = 5.1, 10.8) under dry conditions and 43.7% (5% CI = 35.6, 53.5) under damp conditions. The detectability of oocysts by qPCR over time decreased by 0.5 cycle threshold per 100 days. Finally, a strong correlation between qPCR results and the dose infecting 50% of mice was found; thus, qPCR results may be used as an estimate of the infectivity of soil samples.
Proteomic Phenotyping of Novosphingobium nitrogenifigens Reveals a Robust Capacity for Simultaneous Nitrogen Fixation, Polyhydroxyalkanoate Production, and Resistance to Reactive Oxygen Species
Authors: Smit Anne-Marie , Strabala Timothy J. , Peng Lifeng , Rawson Pisana , Lloyd-Jones Gareth , Jordan T. William 
Published: May 2012

ABSTRACT

Novosphingobium nitrogenifigens
Y88
T
(Y88) is a free-living, diazotrophic
Alphaproteobacterium
, capable of producing 80% of its biomass as the biopolymer polyhydroxybutyrate (PHB). We explored the potential utility of this species as a polyhydroxybutyrate production strain, correlating the effects of glucose, nitrogen availability, dissolved oxygen concentration, and extracellular pH with polyhydroxybutyrate production and changes in the Y88 proteomic profile. Using two-dimensional differential in-gel electrophoresis and tandem mass spectrometry, we identified 217 unique proteins from six growth conditions. We observed reproducible, characteristic proteomic signatures for each of the physiological states we examined. We identified proteins that changed in abundance in correlation with either nitrogen fixation, dissolved oxygen concentration, or acidification of the growth medium. The proteins that correlated with nitrogen fixation were identified either as known nitrogen fixation proteins or as novel proteins that we predict play roles in aspects of nitrogen fixation based on their proteomic profiles. In contrast, the proteins involved in central carbon and polyhydroxybutyrate metabolism were constitutively abundant, consistent with the constitutive polyhydroxybutyrate production that we observed in this species. Three proteins with roles in detoxification of reactive oxygen species were identified in this obligate aerobe. The most abundant protein in all experiments was a polyhydroxyalkanoate granule-associated protein, phasin. The full-length isoform of this protein has a long, intrinsically disordered Ala/Pro/Lys-rich N-terminal segment, a feature that appears to be unique to sphingomonad phasins. The data suggest that Y88 has potential as a PHB production strain due to its aerobic tolerance and metabolic orientation toward polyhydroxybutyrate accumulation, even in low-nitrogen growth medium.
Identification of a Novel Dihydrodaidzein Racemase Essential for Biosynthesis of Equol from Daidzein in Lactococcus sp. Strain 20-92
Authors: Shimada Yoshikazu , Takahashi Masayuki , Miyazawa Norihiro , Abiru Yasuhiro , Uchiyama Shigeto , Hishigaki Haretsugu 
Published: May 2012

ABSTRACT

Equol is metabolized from daidzein, a soy isoflavone, by the gut microflora. In this study, we identified a novel dihydrodaidzein racemase (
l
-DDRC) that is involved in equol biosynthesis in a lactic acid bacterium,
Lactococcus
sp. strain 20-92, and confirmed that histidine-tagged recombinant
l
-DDRC (
l
-DDRC-His) was able to convert both the (
R
)- and (
S
)-enantiomers of dihydrodaidzein to the racemate. Moreover, we showed that recombinant
l
-DDRC-His was essential for
in vitro
equol production from daidzein by a recombinant enzyme mixture and that efficient
in vitro
equol production from daidzein was possible using at least four enzymes, including
l
-DDRC. We also proposed a model of the metabolic pathway from daidzein to equol in
Lactococcus
strain 20-92.
Natural Transformation of Gallibacterium anatis
Authors: Kristensen Bodil M. , Sinha Sunita , Boyce John D. , Bojesen Anders M. , Mell Joshua C. , Redfield Rosemary J. 
Published: May 2012

ABSTRACT

Gallibacterium anatis
is a pathogen of poultry. Very little is known about its genetics and pathogenesis. To enable the study of gene function in
G. anatis
, we have established methods for transformation and targeted mutagenesis. The genus
Gallibacterium
belongs to the
Pasteurellaceae
, a group with several naturally transformable members, including
Haemophilus influenzae
. Bioinformatics analysis identified
G. anatis
homologs of the
H. influenzae
competence genes, and natural competence was induced in
G. anatis
by the procedure established for
H. influenzae
: transfer from rich medium to the starvation medium M-IV. This procedure gave reproducibly high transformation frequencies with
G. anatis
chromosomal DNA and with linearized plasmid DNA carrying
G. anatis
sequences. Both DNA types integrated into the
G. anatis
chromosome by homologous recombination. Targeted mutagenesis gave transformation frequencies of >2 × 10
−4
transformants CFU
−1
. Transformation was also efficient with circular plasmid containing no
G. anatis
DNA; this resulted in the establishment of a self-replicating plasmid. Nine diverse
G. anatis
strains were found to be naturally transformable by this procedure, suggesting that natural competence is common and the M-IV transformation procedure widely applicable for this species. The
G. anatis
genome is only slightly enriched for the uptake signal sequences identified in other pasteurellaceaen genomes, but
G. anatis
did preferentially take up its own DNA over that of
Escherichia coli
. Transformation by electroporation was not effective for chromosomal integration but could be used to introduce self-replicating plasmids. The findings described here provide important tools for the genetic manipulation of
G. anatis
.
Fluorescence-Based Reporter for Gauging Cyclic Di-GMP Levels in Pseudomonas aeruginosa
Authors: Rybtke Morten T. , Borlee Bradley R. , Murakami Keiji , Irie Yasuhiko , Hentzer Morten , Nielsen Thomas E. , Givskov Michael , Parsek Matthew R. , Tolker-Nielsen Tim 
Published: May 2012

ABSTRACT

The increased tolerance toward the host immune system and antibiotics displayed by biofilm-forming
Pseudomonas aeruginosa
and other bacteria in chronic infections such as cystic fibrosis bronchopneumonia is of major concern. Targeting of biofilm formation is believed to be a key aspect in the development of novel antipathogenic drugs that can augment the effect of classic antibiotics by decreasing antimicrobial tolerance. The second messenger cyclic di-GMP is a positive regulator of biofilm formation, and cyclic di-GMP signaling is now regarded as a potential target for the development of antipathogenic compounds. Here we describe the development of fluorescent monitors that can gauge the cellular level of cyclic di-GMP in
P. aeruginosa
. We have created cyclic di-GMP level reporters by transcriptionally fusing the cyclic di-GMP-responsive
cdrA
promoter to genes encoding green fluorescent protein. We show that the reporter constructs give a fluorescent readout of the intracellular level of cyclic di-GMP in
P. aeruginosa
strains with different levels of cyclic di-GMP. Furthermore, we show that the reporters are able to detect increased turnover of cyclic di-GMP mediated by treatment of
P. aeruginosa
with the phosphodiesterase inducer nitric oxide. Considering that biofilm formation is a necessity for the subsequent development of a chronic infection and therefore a pathogenicity trait, the reporters display a significant potential for use in the identification of novel antipathogenic compounds targeting cyclic di-GMP signaling, as well as for use in research aiming at understanding the biofilm biology of
P. aeruginosa
.
Improvement of FK506 Production in Streptomyces tsukubaensis by Genetic Enhancement of the Supply of Unusual Polyketide Extender Units via Utilization of Two Distinct Site-Specific Recombination Systems
Authors: Chen Dandan , Zhang Qi , Zhang Qinglin , Cen Peilin , Xu Zhinan , Liu Wen 
Published: May 2012

ABSTRACT

FK506 is a potent immunosuppressant that has a wide range of clinical applications. Its 23-member macrocyclic scaffold, mainly with a polyketide origin, features two methoxy groups at C-13 and C-15 and one allyl side chain at C-21, due to the region-specific incorporation of two unusual extender units derived from methoxymalonyl-acyl carrier protein (ACP) and allylmalonyl-coenzyme A (CoA), respectively. Whether their intracellular formations can be a bottleneck for FK506 production remains elusive. In this study, we report the improvement of FK506 yield in the producing strain
Streptomyces tsukubaensis
by the duplication of two sets of pathway-specific genes individually encoding the biosyntheses of these two extender units, thereby providing a promising approach to generate high-FK506-producing strains via genetic manipulation. Taking advantage of the fact that
S. tsukubaensis
is amenable to two actinophage (ΦC31 and VWB) integrase-mediated recombination systems, we genetically enhanced the biosyntheses of methoxymalonyl-ACP and allylmalonyl-CoA, as indicated by transcriptional analysis. Together with the optimization of glucose supplementation, the maximal FK506 titer eventually increased by approximately 150% in comparison with that of the original strain. The strategy of engineering the biosynthesis of unusual extender units described here may be applicable to improving the production of other polyketide or nonribosomal peptide natural products that contain pathway-specific building blocks.
Biochemical Characterization of a Novel Haloalkane Dehalogenase from a Cold-Adapted Bacterium
Authors: Drienovska Ivana , Chovancova Eva , Koudelakova Tana , Damborsky Jiri , Chaloupkova Radka 
Published: May 2012

ABSTRACT

A haloalkane dehalogenase, DpcA, from
Psychrobacter cryohalolentis
K5, representing a novel psychrophilic member of the haloalkane dehalogenase family, was identified and biochemically characterized. DpcA exhibited a unique temperature profile with exceptionally high activities at low temperatures. The psychrophilic properties of DpcA make this enzyme promising for various environmental applications.
Detection of Imported Wild Polioviruses and of Vaccine-Derived Polioviruses by Environmental Surveillance in Egypt
Authors: Blomqvist Soile , El Bassioni Laila , El Maamoon Nasr Eman M. , Paananen Anja , Kaijalainen Svetlana , Asghar Humayun , de Gourville Esther , Roivainen Merja 
Published: May 2012

ABSTRACT
Systematic environmental surveillance for poliovirus circulation has been conducted in Egypt since 2000. The surveillance has revealed three independent importations of wild-type poliovirus. In addition, several vaccine-derived polioviruses have been detected in various locations in Egypt. In addition to acute flaccid paralysis (AFP) surveillance, environmental surveillance can be used to monitor the wild poliovirus and vaccine-derived poliovirus circulation in populations in support of polio eradication initiatives.