Key Laboratory of Experimental Marine Biology, Center for Ocean Mega-Science, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266071, China.
Int J Mol Sci. 2019 Aug 16;20(16):4000. doi: 10.3390/ijms20164000.
Tic20 is an important translocon protein that plays a role in protein transport in the chloroplast. The sequence of Tic20 was determined in the lower brown alga . Structural analysis of SjTic20 revealed a noncanonical structure consisting of an N-terminal non-cyanobacterium-originated EF-hand domain (a helix-loop-helix structural domain) and a C-terminal cyanobacterium-originated Tic20 domain. Subcellular localization and transmembrane analysis indicated that SjTic20 featured an "M"-type N-C-terminal orientation, with four transmembrane domains in the innermost membrane of the chloroplast in the microalga , and the EF-hand domain was entirely extruded into the chloroplast stroma. Our study provides information on the structure, localization, and topological features of SjTic20, and further functional analysis of SjTic20 in is needed.
Tic20 是一种重要的易位子蛋白，在叶绿体的蛋白质运输中发挥作用。该序列在低等褐藻中被确定。对 SjTic20 的结构分析揭示了一种非典型的结构，由一个 N 端非蓝细菌起源的 EF 手结构域（一个螺旋-环-螺旋结构域）和一个 C 端蓝细菌起源的 Tic20 结构域组成。亚细胞定位和跨膜分析表明，SjTic20 具有“M”型 N-C 端取向，在微藻的叶绿体最内层膜中有四个跨膜结构域，EF 手结构域完全被挤出到叶绿体基质中。我们的研究提供了 SjTic20 的结构、定位和拓扑特征的信息，需要进一步对 SjTic20 在 中的功能进行分析。
