当前位置： SCI文献检索 > PHYTOCHEMISTRY期刊下所有文献 > Phosphorylation-mediated regulation of a rice ABA responsive element binding factor.

Phosphorylation-mediated regulation of a rice ABA responsive element binding factor.

Abstract：

:OREB1 is a rice ABRE binding factor characterized by the presence of multiple highly-conserved phosphorylation domains (C1, C2, C3, and C4) and two kinase recognition motifs, RXXS/T and S/TXXE/D, within different functional domains. An in vitro kinase assay showed that OREB1 is phosphorylated not only by the SnRK2 kinase, but also by other Ser/Thr protein kinases, such as CaMKII, CKII, and SnRK3. Furthermore, the N-terminal phosphorylation domain C1 was found to be differentially phosphorylated by the SnRK2/SnRK3 kinase and by hyperosmotic/cold stress, suggesting that the C1 domain may function in decoding different signals. The phosphorylation-mediated regulation of OREB1 activity was investigated through mutation of the SnRK2 recognition motif RXXS/T within each phosphorylation module. OREB1 contains a crucial nine-amino acid transactivation domain located near the phosphorylation module C1. Deletion of the C1 domain increased OREB1 activity, whereas mutation of Ser 44, Ser 45, and Ser 48 of the C1 domain to aspartates decreased OREB1 activity. In the C2 domain, a double mutation of Ser 118 and Ser 120 to alanines suppressed OREB1 activity. These findings strongly suggest that selective phosphorylation of the C1 or C2 modules may positively or negatively regulate OREB1 transactivation. In addition, mutation of Ser 385 of the C4 domain to alanines completely abolished the interaction between OREB1 and a rice 14-3-3 protein, GF14d, suggesting that SnRK2-mediated phosphorylation may regulate this interaction. These results indicate that phosphorylation domains of OREB1 are not functionally redundant and regulate at least three different functions, including transactivation activity, DNA binding, and protein interactions. The multisite phosphorylation of OREB1 is likely a key for the fine control of its activity and signal integration in the complex stress signaling network of plant cells.

journal_name

Phytochemistry

journal_title

Phytochemistry

authors

Hong JY,Chae MJ,Lee IS,Lee YN,Nam MH,Kim DY,Byun MO,Yoon IS

doi

10.1016/j.phytochem.2010.10.005

subject

Has Abstract

pub_date

2011-01-01 00:00:00

pages

27-36

issue

eissn

0031-9422

issn

1873-3700

pii

S0031-9422(10)00385-7

journal_volume

pub_type

杂志文章

在线工具

Phosphorylation-mediated regulation of a rice ABA responsive element binding factor.