title: Organization and variation analysis of 5S rDNA in gynogenetic offspring of Carassius auratus red var. (♀) × Megalobrama amblycephala (♂).
abstract: BACKGROUND
  The offspring with 100 chromosomes (abbreviated as GRCC) have been obtained in the first generation of Carassius auratus red var. (abbreviated as RCC, 2n = 100) (♀) × Megalobrama amblycephala (abbreviated as BSB, 2n = 48) (♂), in which the females and unexpected males both are found. Chromosomal and karyotypic analysis has been reported in GRCC which gynogenesis origin has been suggested, but lack genetic evidence.
  
  
  RESULTS
  Fluorescence in situ hybridization with species-specific centromere probes directly proves that GRCC possess two sets of RCC-derived chromosomes. Sequence analysis of the coding region (5S) and adjacent nontranscribed spacer (abbreviated as NTS) reveals that three types of 5S rDNA class (class I; class II and class III) in GRCC are completely inherited from their female parent (RCC), and show obvious base variations and insertions-deletions. Fluorescence in situ hybridization with the entire 5S rDNA probe reveals obvious chromosomal loci (class I and class II) variation in GRCC.
  
  
  CONCLUSIONS
  This paper provides directly genetic evidence that GRCC is gynogenesis origin. In addition, our result is also reveals that distant hybridization inducing gynogenesis can lead to sequence and partial chromosomal loci of 5S rDNA gene obvious variation.
authors: Key Laboratory of Protein Chemistry and Developmental Biology of the State Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410018, People's Republic of China. 30055776@qq.com.
authors: QinBo
authors: Q
authors: Qin
authors: Key Laboratory of Protein Chemistry and Developmental Biology of the State Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410018, People's Republic of China. 627233035@qq.com.
authors: Juan
authors: J
authors: Wang
authors: Key Laboratory of Protein Chemistry and Developmental Biology of the State Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410018, People's Republic of China. 461669793@qq.com.
authors: YuDe
authors: Y
authors: Wang
authors: Key Laboratory of Protein Chemistry and Developmental Biology of the State Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410018, People's Republic of China. liuyun@hunnu.edu.cn.
authors: Yun
authors: Y
authors: Liu
authors: Key Laboratory of Protein Chemistry and Developmental Biology of the State Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha, 410018, People's Republic of China. lsj@hunnu.edu.cn.
authors: ShaoJun
authors: S
authors: Liu
mesh_terms: D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D002875:Chromosomes; D005260:Female; D005399:Fishes / Q000235:genetics*; D056426:Genetic Loci; D014644:Genetic Variation; D006824:Hybridization, Genetic; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D008969:Molecular Sequence Data; D012341:RNA, Ribosomal, 5S / Q000737:chemistry / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D012341:RNA, Ribosomal, 5S