Abstract
Among 2,090 chloroplast proteins identified by computational prediction in Arabidopsis, we collected 3,416 tag-lines disrupted by transposon or T-DNA that encode 1,374 chloroplast proteins. From this collection, we have not only isolated mutants with visible phenotype (apg mutants), but also collected homo-lines without clear phenotypes. By screening of 702 of RIKEN Ds tag-lines, we identified 578 homozygotes with no obvious phenotype, 59 mutants showing abnormal seedling and 62 mutants of which homozygotes were not obtained. Among 43 genes that caused abnormal phenotype, 20 genes existed several alleles with similar phenotypes, suggesting their important role for chloroplast development. 59 mutants that could not obtained homozygotes are valuable resource to understand the roles of plastid development in plant embryogenesis. For the functional analysis of the nuclear-encoded chloroplast proteins that affect abiotic stress response, we isolated several candidates for stress-related chloroplast proteins by screening of 578 homozygotes. We will discuss their possible functions.
