title: A Mutation in GIANT CHLOROPLAST Encoding a PARC6 Homolog Affects Spikelet Fertility in Rice.
abstract: Chloroplasts are not generated de novo but proliferate from a pre-existing population of plastids present in meristematic cells. Chloroplast division is executed by the co-ordinated action of at least two molecular machineries: internal machinery located on the stromal side of the inner envelope membrane and external machinery located on the cytosolic side of the outer envelope membrane. To date, molecular studies of chloroplast division in higher plants have been limited to several species such as Arabidopsis. To elucidate chloroplast division in rice, we performed forward genetics and isolated a mutant displaying large chloroplasts among an ethyl methanesulfonate (EMS)-mutagenized Oryza sativa spp japonica Nipponbare population. Using a map-based approach, this mutation, termed giant chloroplast (gic), was allocated in a gene that encodes a protein that is homologous to Paralog of ARC6 (PARC6), which is known to play a role in chloroplast division. GIC is unique in that it has a long C-terminal extension that is not present in other PARC6 homologs. Characterization of gic phenotypes in a rice field showed that gic exhibited defective growth in seed setting, suggesting that the gic mutant negatively affects the reproductive stage. This report is the first describing a chloroplast division mutant in monocotyledons and its effect on plant development.
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan.
authors: Peter K
authors: PK
authors: Kamau
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan.
authors: Shingo
authors: S
authors: Sano
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan.
authors: Tsuneaki
authors: T
authors: Takami
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan.
authors: Ryo
authors: R
authors: Matsushima
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan.
authors: Masahiko
authors: M
authors: Maekawa
authors: Institute of Plant Science and Resources (IPSR), Okayama University, Kurashiki, Okayama, 710-0046 Japan saka@okayama-u.ac.jp.
authors: Wataru
authors: W
authors: Sakamoto
mesh_terms: D000595:Amino Acid Sequence; D002736:Chloroplasts / Q000378:metabolism / Q000648:ultrastructure; D003001:Cloning, Molecular; D005298:Fertility; D017343:Genes, Plant; D005816:Genetic Complementation Test; D056426:Genetic Loci; D005820:Genetic Testing; D058503:Mesophyll Cells / Q000378:metabolism / Q000648:ultrastructure; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics*; D012275:Oryza / Q000033:anatomy & histology / Q000235:genetics*; D010641:Phenotype; D010788:Photosynthesis; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011058:Pollen / Q000378:metabolism; D011523:Protoplasts / Q000378:metabolism; D019655:Quantitative Trait, Heritable; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
chemical_list: D010940:Plant Proteins
keywords: Chloroplast; Division ring; GIANT CHLOROPLAST; Monocots; Oryza sativa; PARC6