H3K4me3

H3K4me3 shine gyare-gyaren epigenetic zuwa furotin na marufi na DNA Histone H3 wanda ke nuna tri- methylation a ragowar lysine na 4th na furotin H3 na histone kuma galibi yana shiga cikin ka'idojin bayyanar kwayoyin halitta .  Sunan yana nuna ƙarin ƙungiyoyin methyl guda uku ( trimethylation ) zuwa lysine 4 akan furotin H3 na histone .

Ana amfani da H3 don kunshin DNA a cikin sel eukaryotic (ciki har da sel ɗan adam), da gyare-gyare ga histone yana canza damar samun kwayoyin halitta don rubutawa. H3K4me3 yawanci yana da alaƙa da kunna rubutun kwayoyin halitta na kusa. H3K4 trimethylation yana daidaita maganganun kwayoyin halitta ta hanyar gyaran chromatin ta hadaddun NURF .  Wannan ya sa DNA a cikin chromatin ya fi dacewa don abubuwan da aka rubuta, yana ba da damar rubutun kwayoyin halitta da bayyana a cikin tantanin halitta. Musamman ma, ana samun H3K4me3 don ingantaccen tsarin rubutu ta hanyar kawo histone acetylases da nucleosome remodeling enzymes (NURF).  H3K4me3 kuma yana taka muhimmiyar rawa a cikin tsarin tsarin kwayoyin halitta na karfin kwayar halitta da zuriya .  Wannan shi ne saboda ana samun wannan gyare-gyaren tarihi a cikin yankunan DNA da ke hade da haɓakawa da kuma kafa asalin kwayar halitta. 

 Sunayen suna 
H3K4me3 yana nuna trimethylation na lysine 4 a kan histone H3 protein subunit:
Abbre.Ma'anarH3H3 iyali na histonesKdaidaitattun raguwa don lysine4matsayi na amino acid residue (ƙidaya daga N-ƙarshe) NiƘungiyar methyl3yawan kungiyoyin methyl da aka kara
An halicci gyaran H3K4me3 ta hanyar histone methyltransferase (HMT) na lysine wanda ke canja Ƙungiyoyin methyl guda uku zuwa histone H3. H3K4me3 yana da methylated ta hanyar methyltransferase complexes wanda ke dauke da furotin WDR5, wanda ya ƙunshi WD40 maimaitawa furotin motif. WDR5 yana haɗuwa musamman tare da dimethylated H3K4 kuma yana ba da damar ci gaba da methylation ta hanyar methyltransferases, yana ba da izinin ƙirƙirar da karanta gyaran H3K5me3. An nuna aikin WDR5 ana buƙatar shi don kwayoyin halitta na ci gaba, kamar kwayoyin halitta sunayen Hox, waɗanda ke sarrafawa ta hanyar histone methylation.

 Alamar epigenetic 
H3K4me3 gyare-gyaren histone ne da aka saba amfani dashi. H3K4me3 yana daya daga cikin mafi ƙarancin gyare-gyaren histone; duk da haka, yana da wadata sosai a masu tallatawa masu aiki kusa da wuraren farawa na fassarar (TSS)  kuma yana da alaƙa da fassarar. Ana amfani da H3K4me3 azaman lambar histone ko alamar histone a cikin nazarin epigenetic (yawanci ana gano shi ta hanyar chromatin immunoprecipitation) don gano masu gabatar da kwayar halitta masu aiki.

H3K4me3 yana inganta kunna kwayar halitta ta hanyar aikin NURF complex, wani furotin mai rikitarwa wanda ke aiki ta hanyar furotin na yatsa na PHD don sake fasalin chromatin. Wannan ya sa DNA a cikin chromatin ya kasance mai sauƙi don Abubuwan fassarar, yana ba da damar rubutun kwayoyin halitta kuma ya bayyana a cikin tantanin halitta.

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