小鼠CD226(PTA1)的基因克隆及其异型

Molecular cloning of mouse CD226(PTA1) and its isoforms

目的 :克隆小鼠CD2 2 6 (PTA1)分子。方法 :从GenBank中检索出与人CD2 2 6分子在氨基酸水平上有 5 1%同源性的EST序列 ,设计并合成特异性引物 ,采用快速扩增cDNA末端的RACE方法 ,从 4周龄BALB c小鼠的胸腺中扩增小鼠CD2 2 6cDNA序列。结果 :克隆出完整的小鼠CD2 2 6cDNA ,长 2 2 2 3bp ,其中开放读框为 10 0 2bp ,编码含信号肽在内的 333个氨基酸 ,属免疫球蛋白超家族分子 ,较人CD2 2 6分子少了 3个氨基酸 ,在氨基酸水平上有 5 3%的同源性。此外 ,还克隆了小鼠CD2 2 6分子的 3种异型。结论 :成功克隆出小鼠CD2 2 6 (PTA1)cDNA ,并发现 3种异型 ,全面探讨该分子生物学特性 ,进行体内功能实验 ,基因敲除小鼠和转基因小鼠的研究提供了坚实的基础。

Objective:To clone mouse CD226(platelet and T cell activation antigen1,PTA1).Methods:Specific primers were designed and sythesized according to the EST sequence from GenBank,which had 51% homology to human CD226 on the amino acid level.And then,the cDNA of mouse CD226 was cloned from the thymus of 4 week old BALB/c mouse by using RACE technique.Results:The length of mouse CD226 cDNA is 2 223 bp,with the open reading frame(ORF) of 1 002 bp,encoding 333 amino acids,which is 3 amino acids shorter than its counterpart in human.The mouse CD226 belongs to IgSF,and shares 53% homology with human PTA1 on amino acid level.Besides,three isoforms of mouse PTA1 were also cloned at the mean time.Conclusion:The molecular cloning of mouse PTA1 lays the foundation for the in vivo studies on the biological function of this molecule,as well as the studies of this molecule in gene knockout mouse and transgenic mouse.