title: Control of rice grain-filling and yield by a gene with a potential signature of domestication.
abstract: Grain-filling, an important trait that contributes greatly to grain weight, is regulated by quantitative trait loci and is associated with crop domestication syndrome. However, the genes and underlying molecular mechanisms controlling crop grain-filling remain elusive. Here we report the isolation and functional analysis of the rice GIF1 (GRAIN INCOMPLETE FILLING 1) gene that encodes a cell-wall invertase required for carbon partitioning during early grain-filling. The cultivated GIF1 gene shows a restricted expression pattern during grain-filling compared to the wild rice allele, probably a result of accumulated mutations in the gene's regulatory sequence through domestication. Fine mapping with introgression lines revealed that the wild rice GIF1 is responsible for grain weight reduction. Ectopic expression of the cultivated GIF1 gene with the 35S or rice Waxy promoter resulted in smaller grains, whereas overexpression of GIF1 driven by its native promoter increased grain production. These findings, together with the domestication signature that we identified by comparing nucleotide diversity of the GIF1 loci between cultivated and wild rice, strongly suggest that GIF1 is a potential domestication gene and that such a domestication-selected gene can be used for further crop improvement.
authors.affiliation: Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, China.
authors.forename: Ertao
authors.initials: E
authors.lastname: Wang
authors.forename: Jianjun
authors.initials: J
authors.lastname: Wang
authors.forename: Xudong
authors.initials: X
authors.lastname: Zhu
authors.forename: Wei
authors.initials: W
authors.lastname: Hao
authors.forename: Linyou
authors.initials: L
authors.lastname: Wang
authors.forename: Qun
authors.initials: Q
authors.lastname: Li
authors.forename: Lixia
authors.initials: L
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: He
authors.forename: Baorong
authors.initials: B
authors.lastname: Lu
authors.forename: Hongxuan
authors.initials: H
authors.lastname: Lin
authors.forename: Hong
authors.initials: H
authors.lastname: Ma
authors.forename: Guiquan
authors.initials: G
authors.lastname: Zhang
authors.forename: Zuhua
authors.initials: Z
authors.lastname: He
mesh_terms: D002241:Carbohydrates / Q000032:analysis; D018556:Crops, Agricultural / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D002523:Edible Grain / Q000235:genetics*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D007178:Inbreeding; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D021381:Protein Transport
chemical_list: D002241:Carbohydrates; D010940:Plant Proteins