光合成生物の分裂に新たな仕組みを発見～チラコイド膜を形づくるタンパク質が細胞・葉緑体分裂にも関与～

2025-10-10 基礎生物学研究所

図 1　シアノバクテリア(Synechocystis sp. PCC 6803)野生株とCurT欠損変異株細胞のクロロフィル蛍光イメージ

<関連情報>

• https://www.nibb.ac.jp/press/2025/10/10.html
• https://www.nature.com/articles/s41467-025-64163-x

CurT/CURT1タンパク質はシアノバクテリアと緑藻類の細胞分裂と葉緑体分裂の調整に関与している CurT/CURT1 proteins are involved in cell and chloroplast division coordination of cyanobacteria and green algae

Marcel Dann,Eunchul Kim,Konomi Fujimura-Kamada,Vjosa Berisha,Mami Nomura,Anne-Christin Pohland,Mai Watanabe,Matthias Ostermeier,Frederik Sommer,Michael Schroda,Shin-ya Miyagishima & Jun Minagawa
Nature Communications  Published:25 September 2025
DOI:https://doi.org/10.1038/s41467-025-64163-x

Abstract

Plant proteins of the CURVATURE THYLAKOID 1 (CURT1) family and their prokaryotic CurT homologues are key determinants of the three-dimensional structure of the thylakoid membrane systems in chloroplasts and cyanobacteria. As the evolutionary origin of the CURT1/CurT family appears to coincide with the evolution of thylakoids themselves, shaping the thylakoid system has widely been regarded as their primary role. In this study we present strong evidence that CurT, beyond regulation of thylakoid architecture, is involved in cell division and thylakoid fission/partitioning in both Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942, likely through physical interaction with the key cell division protein FtsZ. Similarly, triple mutants of Chlamydomonas reinhardtii CURT1A, B, and C display an asymmetric chloroplast division phenotype, thus suggesting an evolutionary conserved functionality of CurT/CURT1 in cell/chloroplast division in single-celled oxygenic photosynthesizers.