Plastid chaperone HSP90C guides precursor proteins to the SEC translocase for thylakoid transport.
Plastid chaperone HSP90C guides precursor proteins to the SEC translocase for thylakoid transport.
复制标题
DOI：
10.1093/jxb/eraa399
复制
发表时间：
2020-12-31
影响因子：
6.9
通讯作者：
Zhao R
中科院分区：
文献类型：
--
作者：
Jiang T;Mu B;Zhao R
叶绿体基质分子伴侣HSP 90 C直接与类囊体SEC转位酶相互作用，以ATP酶活性依赖的方式指导其客户蛋白进行类囊体转运。叶绿体基质因子参与调节类囊体蛋白靶向知之甚少。我们以前报道，在拟南芥中，基质本地化的伴侣蛋白HSP 90 C（质体热休克蛋白90）与核编码的类囊体腔蛋白PsbO 1（PSII亚基O亚型1）相互作用，并建议在帮助PsbO 1类囊体靶向HSP 90 C的作用。使用在organello运输测定，特别是与模型基板自然表达的基质，我们表明，光，外源性ATP，和HSP 90 C活性所需的Sec依赖性运输的绿色荧光蛋白（GFP）的PsbO 1类囊体靶向序列。使用以前确定的PsbO 1 T200 A突变体，我们提供的证据表明，热休克蛋白90 C和PsbO 1之间更强的相互作用，更好地促进其基质类囊体运输。我们还证明了SecY 1，类囊体SEC转位酶的通道蛋白，在体内特异性地与HSP 90 C相互作用。伴侣ATP酶活性的抑制抑制与SecY 1的PsbO 1 GFP-HSP 90 C复合物的协会。再加上分析的表达和积累的其他几个类囊体蛋白，利用SRP，达特，或SEC的易位途径，我们提出了一个模型，其中HSP 90 C形成一个指导复合物，与类囊体蛋白前体相互作用，并协助其特异性靶向类囊体SEC易位。
The chloroplast stromal chaperone HSP90C interacts directly with thylakoid SEC translocase to direct its client proteins for thylakoid transport in an ATPase activity-dependent manner. Chloroplast stromal factors involved in regulating thylakoid protein targeting are poorly understood. We previously reported that in Arabidopsis thaliana, the stromal-localized chaperone HSP90C (plastid heat shock protein 90) interacted with the nuclear-encoded thylakoid lumen protein PsbO1 (PSII subunit O isoform 1) and suggested a role for HSP90C in aiding PsbO1 thylakoid targeting. Using in organello transport assays, particularly with model substrates naturally expressed in stroma, we showed that light, exogenous ATP, and HSP90C activity were required for Sec-dependent transport of green fluorescent protein (GFP) led by the PsbO1 thylakoid targeting sequence. Using a previously identified PsbO1T200A mutant, we provided evidence that a stronger interaction between HSP90C and PsbO1 better facilitated its stroma–thylakoid trafficking. We also demonstrated that SecY1, the channel protein of the thylakoid SEC translocase, specifically interacted with HSP90C in vivo. Inhibition of the chaperone ATPase activity suppressed the association of the PsbO1GFP–HSP90C complex with SecY1. Together with analyzing the expression and accumulation of a few other thylakoid proteins that utilize the SRP, TAT, or SEC translocation pathways, we propose a model in which HSP90C forms a guiding complex that interacts with thylakoid protein precursors and assists in their specific targeting to the thylakoid SEC translocon.
登录
查看更多内容
叶绿体靶向的 Hsp90 在拟南芥质体发育和胚胎发生中发挥重要作用，可能与 VIPP1 相关。
影响因子：
6.4
作者：
Feng, Juanjuan;Fan, Pengxiang;Li, Yinxin
通讯作者：
Li, Yinxin
影响因子：
4.3
作者：
Frain, Kelly M.;Gangl, Doris;Robinson, Colin
通讯作者：
Robinson, Colin
DOI：
10.1073/pnas.1219229110
发表时间：
2013-02-19
影响因子：
11.1
作者：
Inoue, Hitoshi;Li, Ming;Schnell, Danny J.
通讯作者：
Schnell, Danny J.
影响因子：
7.2
作者：
Biebl, Maximilian M.;Buchner, Johannes
通讯作者：
Buchner, Johannes
影响因子：
11.6
作者：
Cao, D;Lin, Y;Cheng, CL
通讯作者：
Cheng, CL