《植物生理学报》 2018, 54(1): 145-156

拟南芥脂肪酸外运蛋白FAX1影响雄性生殖发育的机制

刘艳艳, 陈雨沁, 石垒, 石建新^*

代谢与发育科学国际合作联合实验室, 上海交通大学生命科学技术学院, 上海200240

通信作者：石建新；E-mail: jianxin.shi@sjtu.edu.cn

摘　要：

拟南芥(Arabidopsis thaliana) FAX1 (fatty acid export 1)定位于质体内膜, 向质体外运输从头合成的脂肪酸, FAX1突变显著降低了生物量和雄性育性, 但FAX1影响植物雄性生殖的机制尚不清楚。我们通过花粉粒染色、正反交和花药半薄切片观察, 发现FAX1突变延缓了绒毡层的降解, 不但影响花粉壁发育和花粉育性, 也影响授粉受精; 通过GUS染色和qRT-PCR检测揭示了FAX1在花早期发育过程的表达上升模式; 通过化学测定和扫描电镜观察发现FAX1突变还影响花器官表面结构的形成。综上所述, FAX1突变从多个方面影响植物雄性生殖发育。

关键词：拟南芥; 脂肪酸外输; 花粉发育; 角质; 蜡质

收稿：2017-09-04   修定：2017-12-25

资助：国家自然科学基金(31671511和31461143001)。

Investigations into the mechanisms underlying the effects of Arabidopsis thaliana fatty acid export 1 (FAX1) in male reproductive development

LIU Yan-Yan, CHEN Yu-Qin, SHI Lei, SHI Jian-Xin^*

Joint International Research Laboratory of Metabolic & Developmental Sciences; School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China

Corresponding author: SHI Jian-Xin; E-mail: jianxin.shi@sjtu.edu.cn

Abstract:

Arabidopsis thaliana fatty acid export 1 (FAX1) is a plastid protein localized in the inner envelope. It exports de novo synthesized fatty acids out of plastid, and its loss-of-function mutation reduces biomass and male fertility significantly. Up to date, the mechanisms underlying FAX1 mutation on male fertility remains obscure. In this study, our cytological analysis and reciprocal cross results revealed that FAX1 mutation not only delayed tapetum degradation that led to impaired pollen wall formation and reduced pollen fertility, but also affected pollination. In addition, GUS staining and qRT-PCR results indicated that FAX1 expression increased significantly along the early stages of flower development. Furthermore, chemical analysis and electronic microscopy observation results showed that sepal surface patterning in FAX1 mutant was impaired as well. Altogether, our findings suggest that FAX1 mutation affects multiple aspects of male reproductive development.

Key words: Arabidopsis thaliana; fatty acid export; pollen development; cutin; wax