title: Structural insights into the coordination of plastid division by the ARC6-PDV2 complex.
abstract: Chloroplasts divide by binary fission, which is accomplished by the simultaneous constriction of the FtsZ ring on the stromal side of the inner envelope membrane, and the ARC5 ring on the cytosolic side of the outer envelope membrane. The two rings are connected and coordinated mainly by the interaction between the inner envelope membrane protein ARC6 and the outer envelope membrane protein PDV2 in the intermembrane space. The underlying mechanism of this coordination is unclear to date. Here, we solved the crystal structure of the intermembrane space region of the ARC6-PDV2 complex. The results indicated that PDV2 inserts its carboxy terminus into a pocket formed in ARC6, and this interaction further induces the dimerization of the intermembrane space regions of two ARC6 molecules. A pdv2 mutant attenuating PDV2-induced ARC6 dimerization showed abnormal morphology of ARC6 rings and compromised chloroplast division in plant cells. Together, our data reveal that PDV2-induced dimerization of ARC6 plays a critical role in chloroplast division and provide insights into the coordination mechanism of the internal and external plastid division machineries.
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Wenhe
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Jinyu
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Qingqing
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Yu
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Jia
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Chuanjing
authors.initials: C
authors.lastname: An
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Yiqiong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Fengjiao
authors.initials: F
authors.lastname: Han
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Chang
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Xiaomin
authors.initials: X
authors.lastname: Liu
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Zhiling
authors.initials: Z
authors.lastname: Zhu
authors.affiliation: Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: You
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Shilong
authors.initials: S
authors.lastname: Fan
authors.affiliation: Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
authors.forename: Maojun
authors.initials: M
authors.lastname: Yang
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Shi-Zhong
authors.initials: SZ
authors.lastname: Luo
authors.affiliation: College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Gao
authors.affiliation: Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Feng
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002736:Chloroplasts / Q000502:physiology*; D018360:Crystallography, X-Ray; D011487:Protein Conformation; D017434:Protein Structure, Tertiary
chemical_list: C502272:ARC6 protein, Arabidopsis; D029681:Arabidopsis Proteins; C582963:plastid division protein PDV2, Arabidopsis