title: Rapid genomic changes in allopolyploids of Carassius auratus red var. (♀) × Megalobrama amblycephala (♂).
abstract: To better understand genomic changes in the early generations after polyploidisation, we examined the chromosomal consequences of genomic merger in allotetraploid hybrids (4 nF1) (AABB, 4n = 148) of Carassius auratus red var. (RCC) (AA, 2n = 100) (♀) × Megalobrama amblycephala (BSB) (BB, 2n = 48) (♂). Complete loss of the paternal 5S rDNA sequence and the expected number of maternal chromosomal loci were found in 4 nF1, suggesting directional genomic changes occurred in the first generations after polyploidisation. Recent studies have reported instability of newly established allotetraploid genomes. To assess this in the newly formed 4 nF1genome, we performed fluorescence in situ hybridisation on an allotetraploid gynogenetic hybrid (4 nG) (AABB, 4n = 148) and an allopentaploid hybrid (5 nH) (AABBB, 5n = 172) from 4 nF1(♀) × BSB (♂) with 5S rDNA gene and centromere probes from RCC, the original diploid parent. The expected numbers of maternal chromosomal loci were found in 4 nG, while chromosomal locus deletions and chromosome recombinations were detected in 5 nH. These observations suggest that abnormal meiosis did not lead to obvious genomic changes in the newly established allotetraploid genomes, but hybridisation with the original diploid parent resulted in obvious genomic changes in the newly established allotetraploid genomes, as was found for the maternal genome.
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: Qinbo
authors.initials: Q
authors.lastname: Qin
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: Zhengfa
authors.initials: Z
authors.lastname: Lai
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: Liu
authors.initials: L
authors.lastname: Cao
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: YuDe
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Protein Chemistry and Fish Developmental Biology of Education Ministry of China, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Liu
mesh_terms: D000818:Animals; D002678:Chimera / Q000235:genetics*; D002875:Chromosomes / Q000235:genetics*; D005260:Female; D056426:Genetic Loci; D016678:Genome; D006054:Goldfish / Q000235:genetics*; D008297:Male; D011123:Polyploidy