title: Fine mapping and candidate gene analysis of the nuclear restorer gene Rfp for pol CMS in rapeseed (Brassica napus L.).
abstract: The Polima (pol) system of cytoplasmic male sterility (CMS) in rapeseed is widely used in China for commercial hybrid seed production. Genetic studies have shown that its fertility restorer gene (Rfp) is monogenic dominant. For fine mapping of the Rfp gene, a near isogenic line comprising 3,662 individuals of BC(14)F(1) generation segregating for the Rfp gene was created. Based on the sequences of two SCAR markers, SCAP0612ST and SCAP0612EM2, developed by Zhao et al. (Genes Genom 30(3):191-196, 2008) and the synteny region of Brassica napus and other Brassica species, 13 markers strongly linked with the Rfp gene were identified. By integrating three of these markers to the published linkage map, the Rfp gene was mapped on linkage group N9 of B. napus. Using these markers, the Rfp locus was narrowed down to a 29.2-kb genomic region of Brassica rapa. Seven open reading frames (ORFs) were predicted in the target region, of these, ORF2, encoding a PPR protein, was the most likely candidate gene of Rfp. These results lay a solid foundation for map-based cloning of the Rfp gene and will be helpful for marker-assisted selection of elite CMS restorer lines.
authors.affiliation: National Key Lab of Crop Genetic Improvement, National Center of Rapeseed Improvement (Wuhan Branch), Huazhong Agricultural University, Wuhan 430070, People's Republic of China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Liu
authors.forename: Pingwu
authors.initials: P
authors.lastname: Liu
authors.forename: Furong
authors.initials: F
authors.lastname: Long
authors.forename: Dengfeng
authors.initials: D
authors.lastname: Hong
authors.forename: Qingbiao
authors.initials: Q
authors.lastname: He
authors.forename: Guangsheng
authors.initials: G
authors.lastname: Yang
mesh_terms: D020029:Base Pairing / Q000235:genetics; D029688:Brassica napus / Q000235:genetics*; D002467:Cell Nucleus / Q000235:genetics*; D020090:Chromosome Segregation / Q000235:genetics; D003593:Cytoplasm / Q000235:genetics*; D017343:Genes, Plant / Q000235:genetics*; D056726:Genetic Association Studies / Q000379:methods*; D008040:Genetic Linkage; D005819:Genetic Markers; D007178:Inbreeding; D018895:Microsatellite Repeats / Q000235:genetics; D058977:Molecular Sequence Annotation; D020161:Physical Chromosome Mapping / Q000379:methods*; D051479:Plant Infertility / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D005819:Genetic Markers