Phosphorylation imayambitsa chowongolera kukula kwa DELLA mu Arabidopsis mwa kulimbikitsa mgwirizano wa histone H2A ndi chromatin.

Mapuloteni a Della ndi ofunikira kwambiriowongolera kukulazomwe zimagwira ntchito yofunika kwambiri pakulamulira chitukuko cha zomera poyankha zizindikiro zamkati ndi zachilengedwe. DELLA imagwira ntchito ngati wowongolera zolemba ndipo imasankhidwa kuti igwirizane ndi olimbikitsa pomangirira ku zinthu zolembera (TFs) ndi histone H2A kudzera mu gawo lake la GRAS. Kafukufuku waposachedwapa wasonyeza kuti kukhazikika kwa DELLA kumayendetsedwa pambuyo pa kumasulira kudzera m'njira ziwiri: polyubiquitination yoyambitsidwa ndi phytohormone gibberellin, zomwe zimapangitsa kuti iwonongeke mwachangu, komanso kuphatikiza ma small ubiquitin-like modifiers (SUMO) kuti iwonjezere kuchulukana kwake. Kuphatikiza apo, ntchito ya DELLA imayendetsedwa mosiyanasiyana ndi ma glycosylation awiri osiyana: kuyanjana kwa DELLA-TF kumakulitsidwa ndi O-fucosylation koma kumaletsedwa ndi kusintha kwa O-linked N-acetylglucosamine (O-GlcNAc). Komabe, ntchito ya DELLA phosphorylation sikudziwika bwino, chifukwa maphunziro am'mbuyomu awonetsa zotsatira zotsutsana, kuyambira zomwe zikusonyeza kuti phosphorylation imalimbikitsa kapena kuchepetsa kuwonongeka kwa DELLA mpaka zina zomwe zikusonyeza kuti phosphorylation simakhudza kukhazikika kwake. Pano, tikupeza malo a phosphorylation mu REPRESSORgawo 1-3(RGA, AtDELLA) yoyeretsedwa ku Arabidopsis thaliana pogwiritsa ntchito kusanthula kwa mass spectrometry ndikuwonetsa kuti phosphorylation ya ma peptide awiri a RGA m'madera a PolyS ndi PolyS/T imalimbikitsa ntchito ya H2A yomangirira komanso yowonjezera RGA. Kugwirizana kwa RGA ndi olimbikitsa omwe akufuna. Chodziwika bwino ndichakuti, phosphorylation sikukhudza kuyanjana kwa RGA-TF kapena kukhazikika kwa RGA. Kafukufuku wathu akuwonetsa momwe mamolekyulu amathandizira ntchito ya DELLA.
Kuti timvetse bwino udindo wa phosphorylation pakuwongolera ntchito ya DELLA, ndikofunikira kuzindikira malo a phosphorylation a DELLA m'thupi ndikuchita kusanthula kwa ntchito m'zomera. Mwa kuyeretsa kwa affinity ya zotulutsa za zomera kutsatiridwa ndi kusanthula kwa MS/MS, tapeza ma phosphosite angapo mu RGA. Pansi pa kusowa kwa GA, phosphorylation ya RHA imawonjezeka, koma phosphorylation sikhudza kukhazikika kwake. Chofunika kwambiri, mayeso a co-IP ndi ChIP-qPCR adawonetsa kuti phosphorylation m'chigawo cha PolyS/T cha RGA imalimbikitsa kuyanjana kwake ndi H2A komanso kugwirizana kwake ndi olimbikitsa omwe akufuna, ndikuwulula njira yomwe phosphorylation imapangira ntchito ya RGA.
RGA imasankhidwa kuti igwire chromatin kudzera mu mgwirizano wa LHR1 subdomain ndi TF kenako imalumikizana ndi H2A kudzera mu PolyS/T region yake ndi PFYRE subdomain, ndikupanga H2A-RGA-TF complex kuti ikhazikitse RGA. Phosphorylation ya Pep 2 m'dera la PolyS/T pakati pa DELLA domain ndi GRAS domain ndi kinase yosadziwika imawonjezera RGA-H2A binding. Puloteni ya rgam2A mutant imachotsa RGA phosphorylation ndikugwiritsa ntchito mawonekedwe osiyana a protein kuti asokoneze H2A binding. Izi zimapangitsa kuti kusagwirizana kwa TF-rgam2A transient kusokonezeke komanso kulekanitsidwa kwa rgam2A kuchokera ku target chromatin. Chithunzichi chikuwonetsa kuponderezedwa kwa transcriptional komwe kumayendetsedwa ndi RGA kokha. Chitsanzo chofananacho chingafotokozedwe pa RGA-mediated transcriptional activation, kupatula kuti H2A-RGA-TF complex ingalimbikitse target gene transcription ndi dephosphorylation ya rgam2A ingachepetse transcription. Chithunzi chosinthidwa kuchokera kwa Huang et al.21.
Deta yonse yowerengera idasanthulidwa pogwiritsa ntchito Excel, ndipo kusiyana kwakukulu kudapezeka pogwiritsa ntchito mayeso a Student's t. Palibe njira zowerengera zomwe zidagwiritsidwa ntchito poyesa kukula kwa chitsanzo. Palibe deta yomwe idachotsedwa mu kusanthula; kuyesaku sikunachitike mwachisawawa; ofufuzawo sanazindikire kufalikira kwa deta panthawi yoyesera ndi kuwunika zotsatira. Kukula kwa chitsanzo kukuwonetsedwa mu nthano ya chithunzi ndi fayilo ya deta yochokera.
Kuti mudziwe zambiri zokhudza kapangidwe ka kafukufukuyu, onani Chidule cha Lipoti Lachilengedwe logwirizana ndi nkhaniyi.
Deta ya mass spectrometry proteomics yaperekedwa ku bungwe la ProteomeXchange kudzera mu malo osungira a PRIDE66 omwe ali ndi chidziwitso cha dataset PXD046004. Deta ina yonse yomwe yapezeka panthawi ya kafukufukuyu yaperekedwa mu Zowonjezera, Mafayilo Owonjezera a Deta, ndi Mafayilo Aawisi a Deta. Deta yochokera ku nkhaniyi yaperekedwa.