title: The SMALL AND ROUND SEED1 (SRS1/DEP2) gene is involved in the regulation of seed size in rice.
abstract: The causal gene of a novel small and round seed mutant 1 (srs1) was identified in rice by map-based cloning and named SMALL AND ROUND SEED 1 (SRS1). The SRS1 gene is identical to the previously identified DENSE AND ERECT PANICLE 2 (DEP2). The SRS1/DEP2 gene encodes a novel protein of 1365 amino acids residues without known functional domains. In the longitudinal direction of the lemma, both cell length and cell number are reduced in srs1-1 compared to the wild type, whereas in the lateral cross section of the lemma, cell length in srs1-1 is greater than that in the wild type, but the cell number in srs1-1 is the same as that in wild type. These results suggest that the small and round seed phenotype of srs1-1 is due to the reduction in both cell length and cell number in the longitudinal direction, and the elongation of the cells in the lateral direction of the lemma. The SRS1 mRNA and proteins are abundant in wild type rice specifically in young organs, namely young leaves, internodes and panicles. Interestingly, the tissues expressing SRS1 are closely related to the tissues that exhibit abnormalities in the srs1 mutants.
authors.affiliation: Department of Bioscience, Fukui Prefectural University, Fukui, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Abe
authors.forename: Keiko
authors.initials: K
authors.lastname: Mieda
authors.forename: Tsuyu
authors.initials: T
authors.lastname: Ando
authors.forename: Izumi
authors.initials: I
authors.lastname: Kono
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yano
authors.forename: Hidemi
authors.initials: H
authors.lastname: Kitano
authors.forename: Yukimoto
authors.initials: Y
authors.lastname: Iwasaki
mesh_terms: D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D023061:Gene Order; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000378:metabolism*; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D012326:RNA Splicing; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000033:anatomy & histology / Q000235:genetics* / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D011993:Recombinant Fusion Proteins