摘要
A PCR survey for Sox genes in a young tetraploid fish Tor douronensis (Teleostei:Cyprinidae) was per-formed to access the evolutionary fates of important functional genes after genome duplication caused by polyploidization event. Totally 13 Sox genes were obtained in Tor douronensis,which represent SoxB,SoxC and SoxE groups. Phylogenetic analysis of Sox genes in Tor douronensis provided evidence for fish-specific genome duplication,and suggested that Sox19 might be a teleost specific Sox gene member. Sequence analysis revealed most of the nucleotide substitutions between duplicated copies of Sox genes caused by tetraploidization event or their orthologues in other species are silent substitutions. It would appear that the sequences are under purifying selective pressure,strongly suggesting that they repre-sent functional genes and supporting selection against all null allele at either of two duplicated loci of Sox4a,Sox9a and Sox9b. Surprising variations of the intron length and similarities of two duplicated copies of Sox9a and Sox9b,suggest that Tor douronensis might be an allotetraploidy.
A PCR survey for Sox genes in a young tetraploid fish Tor douronensis （Teleostei： Cyprinidae） was performed to access the evolutionary fates of important functional genes after genome duplication caused by polyploldizatlon event. Totally 13 Soxgenes were obtained in Tordouronensis, which represent SoxB, SoxC and SoxE groups. PhylogeneUc analysis of Sox genes in Tor douronensis provided evidence for fish-specific genome duplication, and suggested that Sox19 might be a teleost specific Sox gene member. Sequence analysis revealed most of the nucleoUde substitutions between duplicated copies of Soxgenes caused by tetreploldlzatlon event or their orthologues in other species are silent substitutions. It would appear that the sequences are under purifying selective pressure, strongly suggesting that they represent functional genes and supporting selection against all null allele at either of two duplicated loci of Sox4a, Sox9a and Sox9b. Surprising variations of the intron length and similarities of two duplicated copies of Soxga and Sox9b, suggest that Tor douronensis might be an allotetreploidy.
基金
the National Natural Science Foundation of China (Grant No. 30530120)
关键词
四倍体
短基因
基因复制
基因多样性
Tor dourponensis, Sox gene, tetraploidy, genome duplication, gene diversity
