Iiproteni zeDELLA ziyagcinwaabalawuli bokukhulaezidlala indima ephambili ekuphuhlisweni kwezityalo ngokuphendula kwiimpawu zangaphakathi nezangaphandle. Njengabalawuli be-transcriptional, ii-DELLA zibopha izinto ze-transcription (TFs) kunye ne-histone H2A ngokusebenzisa ii-domains zazo ze-GRAS kwaye ziqeshwa ukuba zisebenze kubakhuthazi. Izifundo zakutshanje zibonise ukuba uzinzo lwe-DELLA lulawulwa emva koguqulelo ngeendlela ezimbini: i-polyubiquitination ebangelwa yi-hormone yesityalo.i-gibberellin, nto leyo ekhokelela ekuwohlokeni kwazo ngokukhawuleza, kunye nokudibana ne-ubiquitin-like modifier encinci (SUMO), eyonyusa ukuqokelelana kwazo. Ngaphezu koko, umsebenzi we-DELLA ulawulwa ngokuguquguqukayo ziindlela ezimbini ezahlukeneyo ze-glycosylation: i-O-fucosylation iphucula ukusebenzisana kwe-DELLA-TF, ngelixa ukuguqulwa kwe-O-linked N-acetylglucosamine (O-GlcNAc) kuthintela ukusebenzisana kwe-DELLA-TF. Nangona kunjalo, indima ye-DELLA phosphorylation ayicacanga njengoko izifundo zangaphambili zibonise iziphumo ezingqubanayo, ezinye zithi i-phosphorylation ikhuthaza okanye icinezela ukonakala kwe-DELLA kwaye ezinye zithi i-phosphorylation ayichaphazeli uzinzo lwazo. Apha, sichonga iindawo ze-phosphorylation kwi-GA1-3 repressor (RGA), i-AtDELLA, ehlanjululwe kwi-Arabidopsis thaliana yi-mass spectrometry kwaye sibonisa ukuba i-phosphorylation yee-peptides ezimbini ze-RGA kwiindawo ze-PolyS kunye ne-PolyS/T iphucula umsebenzi we-RGA ngokukhuthaza ukubopha kwe-H2A kunye nokudibana kwe-RGA kunye nabakhuthazi abajolise kuyo. Okuphawulekayo kukuba, i-phosphorylation ayizange ichaphazele ukusebenzisana kwe-RGA-TF okanye uzinzo lwe-RGA. Uphononongo lwethu lubonisa indlela yemolekyuli apho i-phosphorylation ibangela khona umsebenzi we-DELLA.
Uhlalutyo lwethu lwe-mass spectrometric lubonise ukuba zombini iPep1 kunye nePep2 zazine-phosphorylated ephezulu kwi-RGA kwimvelaphi ye-GA-deficient Ga1. Ukongeza kolu phononongo, izifundo ze-phosphoproteomic zikwatyhile i-Pep1 phosphorylation kwi-RGA, nangona indima yayo ingekafundwa53,54,55. Ngokwahlukileyo koko, i-Pep2 phosphorylation ayikachazwa ngaphambili kuba le peptide yayinokubonwa kuphela kusetyenziswa i-RGAGKG transgene. Nangona i-m1A mutation, eyaphelisa i-Pep1 phosphorylation, yanciphisa kancinci umsebenzi we-RGA kwi-planta, yaba nefuthe lokongeza xa idityaniswe ne-m2A ekunciphiseni umsebenzi we-RGA (Umfanekiso oNcedisayo 6). Okubalulekileyo kukuba, i-Pep1 phosphorylation yancitshiswa kakhulu kwi-GA-enhanced sly1 mutant xa ithelekiswa ne-ga1, nto leyo ebonisa ukuba i-GA ikhuthaza i-RGA dephosphorylation, inciphisa umsebenzi wayo. Indlela i-GA ecinezela ngayo i-RGA phosphorylation ifuna uphando olongezelelweyo. Enye into enokwenzeka kukuba oku kufezekiswa ngokulawulwa kwe-protein kinase engaziwayo. Nangona uphando lubonise ukuba ukubonakaliswa kwe-CK1 protein kinase EL1 kuncitshiswa yi-GA kwirayisi41, iziphumo zethu zibonisa ukuba utshintsho oluphezulu lwe-Arabidopsis EL1 homologue (AEL1-4) aluyinciphisi i-RGA phosphorylation. Ngokuvumelana neziphumo zethu, uphando lwakutshanje lwe-phosphoproteomic olusebenzisa imigca ye-Arabidopsis AEL ekhupha kakhulu kunye ne-ael triple mutant aluzange luchonge naziphi na iiproteni ze-DELLA njengeziseko zezi kinases56. Xa sasilungiselela umbhalo-ngqangi, kwaxelwa ukuba i-GSK3, i-gene ebhala i-GSK3/SHAGGY-like kinase kwingqolowa (Triticum aestivum), inokwenza i-phosphorylate DELLA (Rht-B1b)57, nangona i-phosphorylation ye-Rht-B1b yi-GSK3 ingakhange iqinisekiswe kwi-planta. Iimpendulo ze-in vitro enzymatic xa kukho i-GSK3 elandelwa luhlalutyo lwe-mass spectrometry zityhile iindawo ezintathu ze-phosphorylation eziphakathi kwe-DELLA kunye ne-GRAS domains ze-Rht-B1b (Umzobo oNcedisayo 3). Ukutshintshwa kwe-serine ukuya kwi-alanine kuzo zonke iindawo ezintathu ze-phosphorylation kubangele ukwehla komsebenzi we-Rht-B1b kwingqolowa ye-transgenic, ngokuhambelana neziphumo zethu zokuba ukutshintshwa kwe-alanine kwi-Pep2 RGA kunciphisa umsebenzi we-RGA. Nangona kunjalo, uvavanyo lwe-in vitro degradation protein lubonise ngakumbi ukuba i-phosphorylation inokuzinzisa i-Rht-B1b57. Oku kwahlukile kwiziphumo zethu ezibonisa ukuba ukutshintshwa kwe-alanine kwi-Pep2 RGA akutshintshi uzinzo lwayo kwi-planta. I-GSK3 kwingqolowa yi-ortholog yeprotheyini engazweliyo ye-brassinosteroid 2 (BIN2) kwi-Arabidopsis 57. I-BIN2 yi-negative regulator ye-BR signaling, kwaye i-BR ivuselela indlela yayo yokubonisa ngokubangela ukuwohloka kwe-BIN2 58. Sibonise ukuba unyango lwe-BR alunciphisi uzinzo lwe-RGA 59 okanye amanqanaba e-phosphorylation kwi-Arabidopsis (Umfanekiso ongezelelweyo 2), nto leyo ebonisa ukuba i-RGA ayinakwenzeka ukuba i-phosphorylated yi-BIN2.
Zonke iinkcukacha zobungakanani zihlalutywe ngokwezibalo kusetyenziswa i-Excel, kwaye umahluko omkhulu ufunyenwe kusetyenziswa uvavanyo lwe-t lomfundi. Akukho ndlela zezibalo ezisetyenzisiweyo ukumisela ubungakanani besampulu kwangaphambili. Akukho datha ikhutshiweyo kuhlalutyo; uvavanyo aluzange lucwangciswe ngokucwangcisiweyo; kwaye abaphandi babesazi ngolwabiwo ngexesha lovavanyo kunye novavanyo lweziphumo. Ubungakanani besampulu bubonelelwa kwiintsomi zezibalo nakwiifayile zedatha eluhlaza.
Ixesha leposi: Epreli-15-2025