Mapuloteni a DELLA amasungidwazowongolera kukulazomwe zimagwira ntchito yaikulu pakukula kwa zomera poyankha zizindikiro zamkati ndi kunja. Monga owongolera olembera, ma DELLA amamanga ku zinthu zolembera (TFs) ndi histone H2A kudzera m'madomeni awo a GRAS ndipo amalembedwa kuti azitsatira otsatsa. Kafukufuku waposachedwa wasonyeza kuti kukhazikika kwa DELLA kumayendetsedwa pambuyo pomasulira ndi njira ziwiri: polyubiquitination yoyambitsidwa ndi hormone ya zomera.gibberellin, zomwe zimabweretsa kuwonongeka kwawo mofulumira, ndi kugwirizanitsa ndi ubiquitin-like modifier (SUMO), zomwe zimawonjezera kudzikundikira kwawo. Kuphatikiza apo, ntchito ya DELLA imayendetsedwa mwamphamvu ndi njira ziwiri zosiyana za glycosylation: O-fucosylation imathandizira kulumikizana kwa DELLA-TF, pomwe kusintha kwa O-linked N-acetylglucosamine (O-GlcNAc) kumalepheretsa kulumikizana kwa DELLA-TF. Komabe, ntchito ya DELLA phosphorylation sichidziwika bwino monga momwe kafukufuku wam'mbuyomu adawonetsa zotsatira zotsutsana, ndipo ena amanena kuti phosphorylation imalimbikitsa kapena kuchotseratu kuwonongeka kwa DELLA ndipo ena akusonyeza kuti phosphorylation sichikhudza kukhazikika kwawo. Apa, timazindikira malo a phosphorylation mu GA1-3 repressor (RGA), AtDELLA, oyeretsedwa kuchokera ku Arabidopsis thaliana ndi mass spectrometry ndikuwonetsa kuti phosphorylation ya ma peptide awiri a RGA m'madera a PolyS ndi PolyS / T imapangitsa kuti ntchito za RGA zitheke polimbikitsa kumanga kwa H2A ndi RGA kuyanjana ndi olimbikitsa omwe akutsata. Makamaka, phosphorylation sinakhudze kuyanjana kwa RGA-TF kapena kukhazikika kwa RGA. Kafukufuku wathu akuwulula njira ya maselo yomwe phosphorylation imapangitsa kuti DELLA achite.
Kusanthula kwathu kowoneka bwino kunawonetsa kuti Pep1 ndi Pep2 onse anali phosphorylated mu RGA kumbuyo kwa GA-yosowa Ga1. Kuphatikiza pa phunziroli, maphunziro a phosphoproteomic adawululanso Pep1 phosphorylation mu RGA, ngakhale kuti udindo wake sunaphunzirepo53,54,55. Mosiyana ndi zimenezi, Pep2 phosphorylation sichinafotokozedwe kale popeza peptide iyi ikhoza kudziwika pogwiritsa ntchito RGAGKG transgene. Ngakhale kusintha kwa m1A, komwe kunathetsa phosphorylation ya Pep1, kumachepetsa pang'ono ntchito ya RGA mu planta, inali ndi zotsatira zowonjezera pamene ikuphatikizidwa ndi m2A pochepetsa ntchito ya RGA (Supplementary Figure 6). Chofunika kwambiri, Pep1 phosphorylation idachepetsedwa kwambiri mu GA-enhanced sly1 mutant poyerekeza ndi ga1, kutanthauza kuti GA imalimbikitsa RGA dephosphorylation, kuchepetsa ntchito yake. Njira yomwe GA imapondereza RGA phosphorylation imafuna kufufuza kwina. Kuthekera kumodzi ndikuti izi zimatheka kudzera pakuwongolera kwa protein kinase yosadziwika. Ngakhale kuti kafukufuku wasonyeza kuti kufotokoza kwa CK1 protein kinase EL1 kumachepetsedwa ndi GA mu rice41, zotsatira zathu zimasonyeza kuti kusintha kwapamwamba kwa Arabidopsis EL1 homologue (AEL1-4) sikuchepetsa RGA phosphorylation. Pogwirizana ndi zotsatira zathu, kafukufuku waposachedwa wa phosphoproteomic pogwiritsa ntchito mizere ya Arabidopsis AEL overexpressing ndi ael triple mutant sanazindikire mapuloteni aliwonse a DELLA monga magawo a kinases56 awa. Pamene tidakonza zolembazo, zinanenedwa kuti GSK3, jini yomwe imalowetsa GSK3 / SHAGGY-ngati kinase mu tirigu (Triticum aestivum), ikhoza phosphorylate DELLA (Rht-B1b)57, ngakhale kuti phosphorylation ya Rht-B1b ndi GSK3 siinatsimikizidwe mu planta. In vitro enzymatic reactions pamaso pa GSK3 yotsatiridwa ndi misa spectrometry kusanthula kunavumbula malo atatu a phosphorylation omwe ali pakati pa madera a DELLA ndi GRAS a Rht-B1b (Supplementary Fig. 3). Kusintha kwa Serine kwa alanine pamasamba onse atatu a phosphorylation kunachititsa kuti ntchito ya Rht-B1b ikhale yochepa mu tirigu wa transgenic, mogwirizana ndi zomwe tapeza kuti kusintha kwa alanine mu Pep2 RGA kunachepetsa ntchito ya RGA. Komabe, zoyesa zowononga mapuloteni mu vitro zikuwonetsanso kuti phosphorylation imathanso kukhazikika Rht-B1b57. Izi zikusiyana ndi zotsatira zathu zosonyeza kuti kusintha kwa alanine mu Pep2 RGA sikusintha kukhazikika kwake mu planta. GSK3 mu tirigu ndi ortholog ya brassinosteroid-insensitive protein 2 (BIN2) mu Arabidopsis 57. BIN2 ndi wolamulira woipa wa chizindikiro cha BR, ndipo BR imayambitsa njira yake yowonetsera poyambitsa BIN2 kuwonongeka kwa 58. Tinasonyeza kuti chithandizo cha BR sichichepetsa RGA kukhazikika kwa 59 kapena phosphory2 ya phosphory (phosphory 2) Arabid kutanthauza kuti RGA ndiyokayikitsa kukhala phosphorylated ndi BIN2.
Deta yonse yochulukira idawunikidwa pogwiritsa ntchito Excel, ndipo kusiyana kwakukulu kunatsimikiziridwa pogwiritsa ntchito t-test ya Student. Palibe njira zowerengera zomwe zidagwiritsidwa ntchito podziwiratu kukula kwachitsanzo. Palibe deta yomwe idachotsedwa pakuwunika; kuyesera sikunali kwachisawawa; ndipo ochita kafukufukuwo adadziwa za kugawidwako panthawi ya kuyesa ndi kuwunika zotsatira. Kukula kwachitsanzo kumaperekedwa mu nthano zazithunzi komanso m'mafayilo a data.
Nthawi yotumiza: Apr-15-2025