野猪CAPN7基因的克隆、表达和变异分析

Cloning,Expression and Variation Analysis of the Wild Boar CAPN7 Gene

钙蛋白酶是细胞质中主要的蛋白水解酶,在肌肉生长、蛋白转化及嫩化过程中发挥复杂的作用。该研究利用RT-PCR、生物信息学方法克隆野猪(Sus scrofa ussuricus)CAPN7cDNA并进行序列分析,利用相对定量RT-PCR方法研究其组织表达情况和利用PCR-SSCP方法对其进行变异分析。结果表明,野猪CAPN7基因编码区全长2442bp,预期编码813个氨基酸残基,多肽链中存在着calpain家族的催化结构域和催化活性中心;野猪CAPN7不同程度地表达于所检测的12种组织中,在6、9月龄野家杂交猪肌肉组织中的相对表达量高于同一时期的大白猪肌肉组织;所检测到的3种基因型在野猪、民猪和杜洛克中的分布存在着极显著差异。该研究为进一步揭示calpain7的功能提供了分子生物学基础。

Calpains are the key proteases involved in muscle growth, protein transformation and meat tenderization. In this study, CAPN7 cDNA of Wild boar was cloned by RT-PCR, its sequence analysis, expression characterization and polymorphism analysis were performed. The results showed that the full-length coding sequence of Wild boar CAPN7 is 2442 bp long, and encodes a protein of 813 amino acids with the catalytic site of calpain family, whose catalytic triad residues is located at amino acids 290, 458 and 478, respectively. RT-PCR expression analysis indicated that CAPN7 mRNA was ubiquitously expressed in the 12 tissues examined, but the relative abundance was unevenly distributed in tissues. The CAPN7 mRNA levels in muscle of 6 and 9-month-old crossbred pigs were higher than those of Yorkshire pigs at the same ages. In addition, a missense mutation was identified by PCR-SSCP and its distribution in wild boar, Min pig and Duroc was significantly different. The results lay the foundation for further studying the function ofCAPN7 gene.