Functional analysis of the 37 kDa inner envelope membrane polypeptide in chloroplast biogenesis using a Ds‐tagged Arabidopsis pale‐green mutant

• Published in: The Plant journal : for cell and molecular biology Vol. 34; no. 5; pp. 719 - 731
• Main Authors: Motohashi, Reiko, Ito, Takuya, Kobayashi, Masatomo, Taji, Teruaki, Nagata, Noriko, Asami, Tadao, Yoshida, Shigeo, Yamaguchi‐Shinozaki, Kazuko, Shinozaki, Kazuo
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Science Ltd 01-06-2003; Blackwell Science
• Subjects: Amino Acid Sequence; Arabidopsis; Arabidopsis - cytology; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - chemistry; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Base Sequence; Biological and medical sciences; Cell biochemistry; Cell physiology; chloroplast; Chloroplasts - metabolism; Cloning, Molecular; Color; Ds‐tagged line; Fundamental and applied biological sciences. Psychology; Genes, Recessive - genetics; Membrane Proteins - chemistry; Membrane Proteins - genetics; Membrane Proteins - metabolism; methyltransferase; Molecular Sequence Data; Molecular Weight; Mutation - genetics; pale‐green mutant; Phenotype; Plant Leaves - genetics; Plant Leaves - metabolism; Plant physiology and development; Plastids - genetics; Plastids - metabolism; plastoquinone; Plastoquinone - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Sequence Alignment; Membrane protein; methyltransferase; Plastoquinone; Arabidopsis; Biosynthesis; Genetic determinism; Ds-tagged line; Arabidopsis thaliana; pale-green mutant; Regulation(control); Cruciferae; Dicotyledones; Angiospermae; Development; Spermatophyta; Chloroplast
• ISSN: 0960-7412; 1365-313X
• DOI: 10.1046/j.1365-313X.2003.01763.x

Summary
To study the functions of the nuclear genes involved in chloroplast development, we systematically analyzed albino and pale‐green Arabidopsis thaliana mutants by using a two‐component transposon system based on the Ac/Ds element of maize as a mutagen. One of the pale‐green mutants, albino or pale green mutant 1 (designated as apg1), did not survive beyond the seedling stage, when germinated on soil. The chloroplasts of the apg1 plants contained decreased numbers of lamellae with reduced levels of chlorophyll. A gene encoding a 37 kDa polypeptide precursor of the chloroplast inner envelope membrane was disrupted by insertion of the Ds transposon in apg1. The 37 kDa protein had partial sequence similarity to the S‐adenosylmethionine‐dependent methyltransferase. The apg1 plants lacked plastoquinone (PQ), suggesting that the APG1 protein is involved in the methylation step of PQ biosynthesis, which is localized at the envelope membrane. Our results demonstrate the importance of the 37 kDa protein of the chloroplast inner envelope membrane for chloroplast development in Arabidopsis.