title: Arabidopsis phosphatidylglycerophosphate phosphatase 1 involved in phosphatidylglycerol biosynthesis and photosynthetic function.
abstract: Phosphatidylglycerol (PG) is an indispensable lipid constituent of photosynthetic membranes, whose function is essential in photosynthetic activity. In higher plants, the biological function of the last step of PG biosynthesis remains elusive because an enzyme catalyzing this reaction step, namely phosphatidylglycerophosphate phosphatase (PGPP), has been a missing piece in the entire glycerolipid metabolic map. Here, we report the identification and characterization of AtPGPP1 encoding a PGPP in Arabidopsis thaliana. Heterologous expression of AtPGPP1 in yeast Δgep4 complemented growth phenotype and PG-producing activity, suggesting that AtPGPP1 encodes a functional PGPP. The GUS reporter assay showed that AtPGPP1 was preferentially expressed in hypocotyl, vasculatures, trichomes, guard cells, and stigmas. A subcellular localization study with GFP reporter indicated that AtPGPP1 is mainly localized at chloroplasts. A T-DNA-tagged knockout mutant of AtPGPP1, designated pgpp1-1, showed pale green phenotype with reduced PG and chlorophyll contents but no defect in embryo development. In the pgpp1-1 mutant, ultrastructure of plastids indicated defective development of chloroplasts and measurement of photosynthetic parameters showed impaired photosynthetic activity. These results suggest that AtPGPP1 is a primary plastidic PGPP required for PG biosynthesis and photosynthetic function in Arabidopsis.
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.|Molecular and Biological Agricultural Sciences Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.|Graduate Institute of Biotechnology, National Chung-Hsing University, Taichung, Taiwan.
authors.forename: Ying-Chen
authors.initials: YC
authors.lastname: Lin
authors.affiliation: Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kobayashi
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.
authors.forename: Chun-Hsien
authors.initials: CH
authors.lastname: Hung
authors.affiliation: Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Wada
authors.affiliation: Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan.|Biotechnology Centre, National Chung-Hsing University, Taichung, Taiwan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002736:Chloroplasts / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D010715:Phosphatidylglycerols / Q000096:biosynthesis* / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis / Q000235:genetics / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D004269:DNA, Bacterial; D010715:Phosphatidylglycerols; C036483:T-DNA; C034358:phosphatidylglycerophosphate; D010744:Phosphoric Monoester Hydrolases
keywords: 
  Arabidopsis thaliana
  ; chloroplast; glycerolipid; lipid phosphate phosphatase; phosphatidylglycerol; phosphatidylglycerophosphate phosphatase; photosynthesis