The maize tha4 gene functions in sec-independent protein transport in chloroplasts and is related to hcf106, tatA, and tatB.
The maize tha4 gene functions in sec-independent protein transport in chloroplasts and is related to hcf106, tatA, and tatB.
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DOI：
10.1083/jcb.147.2.267
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发表时间：
1999-10-18
期刊：
影响因子：
--
通讯作者：
Barkan A
中科院分区：
文献类型：
--
作者：
Walker MB;Roy LM;Coleman E;Voelker R;Barkan A
蛋白质通过多种机制在叶绿体类囊体膜上易位。一些蛋白质参与来自细菌SecA输出系统的易位机制，需要与叶绿体定位的SecA同源物相互作用。其他蛋白质参与的机制是独立于seca，但需要跨膜的pH梯度。最近，在细菌中发现了与Δ pH机制相对应的机制。遗传学研究表明，参与该机制的一种玉米蛋白HCF106在结构和功能上都与细菌tatA和tatB基因产物相关。我们在这里描述了在Δ pH机制中起作用的第二个玉米基因的突变表型和分子克隆。这个基因，类囊体组装4 (tha4)，是参与Δ pH通路的蛋白质易位所必需的。tha4基因产物的序列与玉米hcf106基因和细菌tatA和tatB基因的序列相似。序列比较表明，tha4更接近tatA，而hcf106更接近tatB。这些发现支持了这种独立的易位机制在细菌内共生体的真核细胞器进化过程中高度保守的观点。
Proteins are translocated across the chloroplast thylakoid membrane by a variety of mechanisms. Some proteins engage a translocation machinery that is derived from the bacterial Sec export system and require an interaction with a chloroplast-localized SecA homologue. Other proteins engage a machinery that is SecA-independent, but requires a transmembrane pH gradient. Recently, a counterpart to this Δ pH mechanism was discovered in bacteria. Genetic studies revealed that one maize protein involved in this mechanism, HCF106, is related in both structure and function to the bacterial tatA and tatB gene products. We describe here the mutant phenotype and molecular cloning of a second maize gene that functions in the Δ pH mechanism. This gene, thylakoid assembly 4 (tha4), is required specifically for the translocation of proteins that engage the Δ pH pathway. The sequence of the tha4 gene product resembles those of the maize hcf106 gene and the bacterial tatA and tatB genes. Sequence comparisons suggest that tha4 more closely resembles tatA, and hcf106 more closely resembles tatB. These findings support the notion that this sec-independent translocation mechanism has been highly conserved during the evolution of eucaryotic organelles from bacterial endosymbionts.
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影响因子：
56.9
作者：
Settles, AM;Yonetani, A;Martienssen, R
通讯作者：
Martienssen, R
针对叶绿体类囊体膜中SEC和Delta pH蛋白传输系统的决定因素和提议的进化基础。
DOI：
10.1083/jcb.136.4.823
发表时间：
1997-02-24
期刊：
The Journal of cell biology
影响因子：
--
作者：
Henry R;Carrigan M;McCaffrey M;Ma X;Cline K
通讯作者：
Cline K
影响因子：
11.4
作者：
Santini, CL;Ize, B;Wu, LF
通讯作者：
Wu, LF
影响因子：
19
作者：
Settles, AM;Martienssen, R
通讯作者：
Martienssen, R
DOI：
10.1073/pnas.90.17.7980
发表时间：
1993-09-01
影响因子：
11.1
作者：
AHN, S;TANKSLEY, SD
通讯作者：
TANKSLEY, SD