Arabidopsis nitrate reductase activity is stimulated by the E3 SUMO ligase AtSIZ1

被引：164

作者：

Park, Bong Soo ^{[1
,2
]}

Song, Jong Tae ^{[3
]}

Seo, Hak Soo ^{[1
,2
,4
]}

机构：

[1] Seoul Natl Univ, Dept Plant Sci, Res Inst Agr & Life Sci, Seoul 151921, South Korea

[2] Seoul Natl Univ, Plant Genom & Breeding Inst, Seoul 151921, South Korea

[3] Kyungpook Natl Univ, Sch Appl Biosci, Taegu 702701, South Korea

[4] Seoul Natl Univ, BioMAX Inst, Seoul 151818, South Korea

来源：

NATURE COMMUNICATIONS | 2011年 / 2卷

关键词：

REGULATORY PHOSPHORYLATION SITE; 14-3-3; PROTEINS; IN-VIVO; SUMOYLATION; NITRITE; TRANSCRIPTION; MUTATION; ENZYME; CONJUGATION; ACTIVATION;

D O I：

10.1038/ncomms1408

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Small ubiquitin-related modifier (SUMO) is a small polypeptide that modulates protein activity and regulates hormone signalling, abiotic and biotic responses in plants. Here we show that AtSIZ regulates nitrogen assimilation in Arabidopsis through its E3 SUMO ligase function. Dwarf plants of siz1-2 flower early, show abnormal seed development and have high salicylic acid content and enhanced resistance to bacterial pathogens. These mutant phenotypes are reverted to wild-type phenotypes by exogenous ammonium but not by nitrate, phosphate or potassium. Decreased nitrate reductase activity in siz1-2 plants resulted in low nitrogen concentrations, low nitric oxide production and high nitrate content in comparison with wild-type plants. The nitrate reductases, NIA1 and NIA2, are sumoylated by AtSIZ1, which dramatically increases their activity. Both sumoylated and non-sumoylated NIA1 and NIA2 can form dimers. Our results indicate that AtSIZ1 positively controls nitrogen assimilation by promoting sumoylation of NRs in Arabidopsis.

引用

页数：10

共 56 条

[1] Covalent attachment of the SUMO-1 protein to the negative regulatory domain of the c-Myb transcription factor modifies its stability and transactivation capacity [J].