RRC ID 6161
Author Garcia C, Khan NZ, Nannmark U, Aronsson H.
Title The chloroplast protein CPSAR1, dually localized in the stroma and the inner envelope membrane, is involved in thylakoid biogenesis.
Journal Plant J.
Abstract Thylakoid biogenesis is a crucial step for plant development involving the combined action of many cellular actors. CPSAR1 is shown here to be required for the normal organization of mature thylakoid stacks, and ultimately for embryo development. CPSAR1 is a chloroplast protein that has a dual localization in the stroma and the inner envelope membrane, according to microscopy studies and subfractionation analysis. CPSAR1 is close to the Obg nucleotide binding protein subfamily and displays GTPase activity, as demonstrated by in vitro assays. Disruption of the CPSAR1 gene via T-DNA insertion results in the arrest of embryo development. In addition, transmission electron microscopy analysis indicates that mutant embryos are unable to develop thylakoid membranes, and remain white. Unstacked membrane structures resembling single lamellae accumulate in the stroma, and do not assemble into mature thylakoid stacks. CPSAR1 RNA interference induces partially developed thylakoids leading to pale-green embryos. Altogether, the presented data demonstrate that CPSAR1 is a protein essential for the formation of normal thylakoid membranes, and suggest a possible involvement in the initiation of vesicles from the inner envelope membrane for the transfer of lipids to the thylakoids.
Volume 63(1)
Pages 73-85
Published 2010-7-1
DOI 10.1111/j.1365-313X.2010.04225.x
PMID 20408996
MeSH Arabidopsis / embryology* Arabidopsis / enzymology Arabidopsis / genetics Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism* DNA, Bacterial / genetics GTP Phosphohydrolases / genetics GTP Phosphohydrolases / metabolism* Gene Expression Regulation, Developmental Gene Expression Regulation, Plant Intracellular Membranes / metabolism Membrane Proteins / genetics Membrane Proteins / metabolism* Microscopy, Electron, Transmission Mutagenesis, Insertional RNA Interference Thylakoids / ultrastructure*
IF 5.775
Times Cited 29
Arabidopsis / Cultured plant cells, genes pst00621