中文摘要：

目的：在pET32a原核表达载体中表达融合myc-6his标签的靶向性甲基化酶B1-3a并进行鉴定。方法：以含有B1．3a基因的pcDNA4．0-B1-3a-myc-6his质粒为模板，通过PCR的方法扩增获得融合有myc-6his标签序列的目的区段B1-3a，然后克隆入表达载体pET32a；以SDS-PAGE和Westernblot方法对表达产物进行鉴定。结果：表达产物中在分子量43kD左右可见与目的蛋白分子量相符的条带，该条带可被6his标签单克隆抗体特异识别。结论：正确构建了靶向性甲基化酶B1-3a的原核表达载体，靶向性甲基化酶能够在pET32a中成功表达.

英文摘要：

Objective： To clone and express the targeting methyltranferase B 1-3a gene fused with myc-6his tag in prokaryotic expression system and to identify the protein of fused expression. Methods： The B1-3a gene was amplified from pcDNA4.0- B1-3a- his-6myc plasmid with PCR method and cloned into the expression vector pET32a. The expression product was analyzed with SDS-PAGE and Western blot. Results： A positive protein band with molecular weight about 43 kD was found in the expression product, which is accordant with interest protein, and this band could be specifically recognized by anti-6his monoclonal antibody. Conclusion： The targeting DNA methyltransferase B1-3a was cloned into the expression vector correctly and expressed successfully in prokaryotic expression system.