The role of the transit peptide in the routing of precursors toward different chloroplast compartments.
The role of the transit peptide in the routing of precursors toward different chloroplast compartments.
复制标题
转运肽在前体流向不同叶绿体区室中的作用。
DOI：
10.1016/0092-8674(86)90657-4
复制
发表时间：
1986
期刊：
影响因子：
64.5
通讯作者：
Weisbeek,P
中科院分区：
文献类型：
--
作者：
Smeekens,S;Bauerle,C;Hageman,J;Keegstra,K;Weisbeek,P
利用嵌合蛋白研究了转运肽在叶绿体内输入蛋白路径中的作用，其中核编码的铁氧还蛋白和质体蓝蛋白前体的转运肽被交换。重组叶绿体系统的导入和定位实验表明，铁氧还蛋白转运肽将成熟质体蓝素从其正确位置（类囊体腔）引导至基质。利用质体蓝素转运肽-成熟铁氧还蛋白嵌合体，加工中间体在进入管腔的途中被阻止。我们提出了质体蓝蛋白转运肽的双结构域假设：第一个结构域在叶绿体输入过程中起作用，而第二个结构域负责穿过类囊体膜的运输。因此，转运肽不仅将蛋白质靶向叶绿体，而且还是其随后在细胞器内定位的主要决定因素。
The role of the transit peptide in the routing of imported proteins inside the chloroplast was investigated with chimeric proteins in which the transit peptides for the nuclear-encoded ferredoxin and plastocyanin precursors were exchanged. Import and localization experiments with a reconstituted chloroplast system show that the ferredoxin transit peptide directs mature plastocyanin away from its correct location, the thylakoid lumen, to the stroma. With the plastocyanin transit peptide-mature ferredoxin chimera, a processing intermediate is arrested on its way to the lumen. We propose a two domain hypothesis for the plastocyanin transit peptide: the first domain functions in the chloroplast import process, whereas the second is responsible for transport across the thylakoid membrane. Thus, the transit peptide not only targets proteins to the chloroplast, but also is a major determinant in their subsequent localization within the organelle.