Ana adana sunadaran DELLAmasu kula da girmawanda ke taka muhimmiyar rawa wajen bunkasa tsire-tsire don amsa alamun ciki da waje. A matsayin masu kula da rubuce-rubuce, DELLAs suna ɗaure ga abubuwan rubutu (TFs) da histone H2A ta yankunansu na GRAS kuma ana ɗaukar su don yin aiki akan masu tallata. Binciken da aka yi kwanan nan ya nuna cewa ana daidaita daidaiton DELLA bayan fassarar ta hanyoyi biyu: polyubiquitation wanda aka haifar da hormone shuka.gibberellin, wanda ke haifar da lalatawar su da sauri, da haɗuwa tare da ƙananan kayan aiki masu kama da ubiquitin (SUMO), wanda ke ƙara yawan tarin su. Bugu da ƙari, ana sarrafa ayyukan DELLA da ƙarfi ta hanyoyi daban-daban na glycosylation: O-fucosylation yana haɓaka hulɗar DELLA-TF, yayin da O-linked N-acetylglucosamine (O-GlcNAc) gyara yana hana hulɗar DELLA-TF. Duk da haka, aikin DELLA phosphorylation ba shi da tabbas kamar yadda binciken da aka yi a baya ya nuna sakamako masu cin karo da juna, tare da wasu suna nuna cewa phosphorylation yana inganta ko rage lalata DELLA da wasu suna nuna cewa phosphorylation ba ya shafar kwanciyar hankali. Anan, mun gano wuraren phosphorylation a cikin GA1-3 repressor (RGA), AtDELLA, wanda aka tsarkake daga Arabidopsis thaliana ta hanyar spectrometry na taro kuma yana nuna cewa phosphorylation na peptides na RGA guda biyu a cikin yankunan PolyS da PolyS / T yana haɓaka ayyukan RGA ta hanyar inganta haɗin H2A da haɗin gwiwar RGA tare da masu ci gaba. Musamman, phosphorylation bai shafi hulɗar RGA-TF ko kwanciyar hankali na RGA ba. Bincikenmu yana bayyana tsarin kwayoyin halitta wanda phosphorylation ke haifar da ayyukan DELLA.
Binciken mu na spectrometric na mu ya nuna cewa duka Pep1 da Pep2 sun kasance masu phosphorylate sosai a cikin RGA a cikin GA-rashin Ga1. Baya ga wannan binciken, nazarin phosphoproteomic ya kuma bayyana Pep1 phosphorylation a cikin RGA, kodayake ba a yi nazarin rawar da ta taka ba tukuna53,54,55. Sabanin haka, Pep2 phosphorylation ba a bayyana a baya ba tunda ana iya gano wannan peptide ta amfani da transgene na RGAGKG. Kodayake maye gurbin m1A, wanda ya soke Pep1 phosphorylation, kawai ya rage yawan ayyukan RGA a cikin planta, yana da tasiri mai mahimmanci lokacin da aka haɗa shi da m2A a rage ayyukan RGA (Ƙarin Hoto 6). Mahimmanci, Pep1 phosphorylation ya ragu sosai a cikin GA-enhanced sly1 mutant idan aka kwatanta da ga1, yana nuna cewa GA yana inganta RGA dephosphorylation, rage ayyukansa. Hanyar da GA ke danne RGA phosphorylation yana buƙatar ƙarin bincike. Wata yuwuwar ita ce ana samun wannan ta hanyar ka'idodin furotin kinase wanda ba a tantance ba. Kodayake nazarin ya nuna cewa bayanin furotin CK1 kinase EL1 ya ragu da GA a cikin shinkafa41, sakamakonmu ya nuna cewa maye gurbi na Arabidopsis EL1 homologue (AEL1-4) ba ya rage RGA phosphorylation. Dangane da sakamakonmu, wani binciken phosphoproteomic na baya-bayan nan ta amfani da layin Arabidopsis AEL masu wuce gona da iri da kuma mutant ael sau uku bai gano wani sunadaran DELLA a matsayin tushen waɗannan kinases56 ba. Lokacin da muka shirya rubutun, an ba da rahoton cewa GSK3, kwayar halittar GSK3/SHAGGY-kamar kinase a cikin alkama (Triticum aestivum), na iya phosphorylate DELLA (Rht-B1b)57, kodayake phosphorylation na Rht-B1b ta GSK3 ba a tabbatar da shi ba a cikin planta. In vitro enzymatic halayen a gaban GSK3 bi da taro spectrometry bincike bayyana uku phosphorylation sites tsakanin DELLA da GRAS domains na Rht-B1b (Ƙarin Hoto 3). Serine zuwa alanine musanya a duk rukunin phosphorylation guda uku ya haifar da raguwar ayyukan Rht-B1b a cikin alkama transgenic, daidai da bincikenmu cewa maye gurbin alanine a cikin Pep2 RGA ya rage ayyukan RGA. Koyaya, ƙididdige lalata lalata furotin a cikin vitro sun ƙara nuna cewa phosphorylation kuma na iya daidaita Rht-B1b57. Wannan ya bambanta da sakamakon mu yana nuna cewa maye gurbin alanine a cikin Pep2 RGA ba ya canza kwanciyar hankali a cikin planta. GSK3 a cikin alkama shine ortholog na brassinosteroid-insensitive protein 2 (BIN2) a cikin Arabidopsis 57. BIN2 shine mummunan tsari na siginar BR, kuma BR yana kunna hanyar siginar ta ta hanyar haifar da lalata BIN2 58. Mun nuna cewa BR magani baya rage RGA RGA 59 ko phosppleidation matakan da aka nuna a cikin Larabci matakan RGA. mai yuwuwa BIN2 ya zama sinadarin phosphorylated.
Dukkan bayanai masu ƙididdigewa an ƙididdige su ta hanyar amfani da Excel, kuma an ƙaddara bambance-bambance masu mahimmanci ta amfani da t-test Student. Ba a yi amfani da hanyoyin ƙididdiga ba don tantance girman samfurin. Babu bayanai da aka cire daga bincike; gwajin ba a kayyade ba; kuma masu binciken sun san abin da aka raba a lokacin gwaji da kimanta sakamakon. Ana ba da nau'i-nau'i masu girma a cikin tatsuniyoyi na adadi da kuma a cikin fayilolin bayanai na asali.
Lokacin aikawa: Afrilu-15-2025