文献类型： 外文期刊

作者： Li LiJuan ¹ ; Ren Fei ² ; Wei PengCheng ¹ ; Chen QiJun ¹ ; Chen Jia ¹ ; Wang XueChen ¹ ;

作者机构： 1.China Agr Univ, Coll Biol Sci, State Key Lab Plant Physiol & Biochem, Beijing 100193, Peoples R China

2.Beijing Acad Agr & Forestry Sci, Inst Forestry & Pomol, Beijing 100093, Peoples R China

关键词： Arabidopsis;osmotic stress;tonoplast intrinsic proteins;endoplasmic reticulum

期刊名称：CHINESE SCIENCE BULLETIN （ 影响因子：1.649； 五年影响因子：1.738 ）

ISSN： 1001-6538

年卷期： 2011 年 56 卷 33 期

页码：

收录情况： SCI

摘要： Aquaporins are implicated in a wide variety of plant physiological processes, although the mechanisms involved in their regulation are not fully understood. To gain further insight into the regulatory factors involved in this process, we used a yeast two-hybrid system to screen for potential binding partners to the Arabidopsis tonoplast intrinsic protein (TIP) AtTIP1;1. This was the first protein identified to be associated with high water permeability in vacuolar membranes from Arabidopsis thaliana. Using AtTIP1;1 as bait, a novel binding protein was identified in both yeast and plant cells. This prey protein, named AtSM34, was a 309 aa polypeptide with a predicted molecular mass of 34 kD and contained a single MYB/SANT-like domain. AtSM34 promoter:: GUS histochemical staining analysis detected AtSM34 expression in flowers, stems and leaves, particularly in the vascular tissues, in response to osmotic stress. AtSM34 expression was localized in the endoplasmic reticulum membrane, and sequence deletion analysis revealed that the N-terminal coding region (amino acids 1-83) was critical for this localization. Overexpression of AtSM34 resulted in hypersensitivity to exogenous mannitol, sorbitol and abscisic acid, and caused a significant delay in germination. AtSM34 interacted with AtTIP1;2 and AtTIP2;1, which are essential proteins for modulation of tonoplast permeability and highly expressed in germinating seedlings. These data indicate AtSM34 is a novel TIPs binding protein involved in the osmotic stress response of seedlings at an early stage of development.