6BHP

Crystal structure of the Chlamydomonas reinhardtii LCI1 channel

6BHP の概要

• エントリーDOI: 10.2210/pdb6bhp/pdb
• 分子名称: Membrane protein, MERCURY (II) ION, CARBON DIOXIDE (3 entities in total)
• 機能のキーワード: channel, co2-concentrating mechanism, microalgae, membrane protein
• 由来する生物種: Chlamydomonas reinhardtii (Chlamydomonas smithii)
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 67199.97

構造登録者

Chou, T.-H.,Radhakrishnan, A. (登録日: 2017-10-31, 公開日: 2018-11-07, 最終更新日: 2024-05-15)

主引用文献

Kono, A.,Chou, T.H.,Radhakrishnan, A.,Bolla, J.R.,Sankar, K.,Shome, S.,Su, C.C.,Jernigan, R.L.,Robinson, C.V.,Yu, E.W.,Spalding, M.H.
Structure and function of LCI1: a plasma membrane CO 2 channel in the Chlamydomonas CO 2 concentrating mechanism.
Plant J., 102:1107-1126, 2020

PubMed Abstract: Microalgae and cyanobacteria contribute roughly half of the global photosynthetic carbon assimilation. Faced with limited access to CO in aquatic environments, which can vary daily or hourly, these microorganisms have evolved use of an efficient CO concentrating mechanism (CCM) to accumulate high internal concentrations of inorganic carbon (C ) to maintain photosynthetic performance. For eukaryotic algae, a combination of molecular, genetic and physiological studies using the model organism Chlamydomonas reinhardtii, have revealed the function and molecular characteristics of many CCM components, including active C uptake systems. Fundamental to eukaryotic C uptake systems are C transporters/channels located in membranes of various cell compartments, which together facilitate the movement of C from the environment into the chloroplast, where primary CO assimilation occurs. Two putative plasma membrane C transporters, HLA3 and LCI1, are reportedly involved in active C uptake. Based on previous studies, HLA3 clearly plays a meaningful role in HCO transport, but the function of LCI1 has not yet been thoroughly investigated so remains somewhat obscure. Here we report a crystal structure of the full-length LCI1 membrane protein to reveal LCI1 structural characteristics, as well as in vivo physiological studies in an LCI1 loss-of-function mutant to reveal the C species preference for LCI1. Together, these new studies demonstrate LCI1 plays an important role in active CO uptake and that LCI1 likely functions as a plasma membrane CO channel, possibly a gated channel.

PubMed: 32168387
DOI: 10.1111/tpj.14745

実験手法

X-RAY DIFFRACTION (3.209 Å)