红鲫Sox4基因保守区的克隆与序列分析

Isolation and Sequence Analysis of Sox4 Gene HMG Box in the Red Crucian Carp

目的为进一步全面理解鱼类Sox基因的复制与进化,从红鲫基因组DNA中克隆Sox基因HMG盒保守区。方法参照Sox基因HMG盒保守区的氨基酸序列设计一对兼并引物,以红鲫基因组DNA为模板进行PCR扩增,并对扩增产物进行亚克隆和测序。结果获得2个序列(序列Ⅰ和序列Ⅱ)。同源性比较显示,序列Ⅰ和序列Ⅱ编码的氨基酸序列均与小鼠Sox4的同源性最高,分别为88.9%和90.7%;氨基酸序列排序比较,序列Ⅰ和序列Ⅱ也都与人Sox4的同源性最高。结果表明,红鲫序列Ⅰ和序列Ⅱ均是小鼠、人Sox4基因的直向同源基因,分别命名为RcSox4-1和RcSox4-2。结论Sox4基因在红鲫进化过程中发生了基因复制,Sox4基因复制可能发生在红鲫、斑马鱼及草鱼分化之前。

Objective To further understand the duplication and evolution of FOx genes of the fish, the HMG boxes of FOx genes were cloned from genomic DNA of the red crucian carp. Methods Genomic DNA from the red crucian carp was used as the template for PCR amplification using degenerate primers designed on the basis of the amino acid sequences of the HMG boxes. PCR products were subeloned and sequenced. Results The sequencing results showed that two sequences were obtained （sequence Ⅰ and sequence n ） . At the amino acid level, sequence Ⅰ and sequence Ⅱ shared the highest identities with the mouse Sox4, 88.9% and 90.1%, respectively. Alignments of amino acid sequences indicated that sequence Ⅰ and sequence Ⅱ also shared the highest identities with the human Sox4. The results suggest that both sequence Ⅰand sequence Ⅱ are orthologues of the Sox4 gene of mouse and human, which were named RcSox4- 1 and RcSox4 - 2, respectively. Conclusions Sox4 gene has been duplicated during the evolution of the red crucian carp lineage. The duplication of Sox4 may occur before the divergence of red crucian carp, zebratish and grass carp.