title: Molecular cloning of Sdr4, a regulator involved in seed dormancy and domestication of rice.
abstract: Seed dormancy provides a strategy for flowering plants to survive adverse natural conditions. It is also an important agronomic trait affecting grain yield, quality, and processing performance. We cloned a rice quantitative trait locus, Sdr4, which contributes substantially to differences in seed dormancy between japonica (Nipponbare) and indica (Kasalath) cultivars. Sdr4 expression is positively regulated by OsVP1, a global regulator of seed maturation, and in turn positively regulates potential regulators of seed dormancy and represses the expression of postgerminative genes, suggesting that Sdr4 acts as an intermediate regulator of dormancy in the seed maturation program. Japonica cultivars have only the Nipponbare allele (Sdr4-n), which endows reduced dormancy, whereas both the Kasalath allele (Srd4-k) and Sdr4-n are widely distributed in the indica group, indicating prevalent introgression. Srd4-k also is found in the wild ancestor Oryza rufipogon, whereas Sdr4-n appears to have been produced through at least two mutation events from the closest O. rufipogon allele among the accessions examined. These results are discussed with respect to possible selection of the allele during the domestication process.
authors.affiliation: National Institute of Agrobiological Sciences, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Sugimoto
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: Kaworu
authors.initials: K
authors.lastname: Ebana
authors.forename: Akio
authors.initials: A
authors.lastname: Miyao
authors.forename: Hirohiko
authors.initials: H
authors.lastname: Hirochika
authors.forename: Naho
authors.initials: N
authors.lastname: Hara
authors.forename: Kanako
authors.initials: K
authors.lastname: Ishiyama
authors.forename: Masatomo
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ban
authors.forename: Tsukaho
authors.initials: T
authors.lastname: Hattori
authors.forename: Masahiro
authors.initials: M
authors.lastname: Yano
mesh_terms: D000483:Alleles; D001483:Base Sequence; D003001:Cloning, Molecular; D018556:Crops, Agricultural / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D017343:Genes, Plant; D005816:Genetic Complementation Test; D054643:INDEL Mutation; D008969:Molecular Sequence Data; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism; D010802:Phylogeny; D030821:Plants, Genetically Modified; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D018749:RNA, Plant