[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of ...[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of Wuzhishan miniature pig as the template, three pairs of primers were designed by the reported cDNA sequence of porcine GHRH, and cDNA was also amplified by RT-PCR. After being recovered and purified, PCR products were ligated to pMD18-T and then transformed into Escherichia coli DH5a. The transformation products were analyzed by PCR and double enzyme digestion to screen positive clones, and the positive clones were sequenced after identification in LB liquid medium. [ Result] cDNA of Wuzhishan miniature pig GHRH receptor gene was obtained successfully, and its length was 1 577 bp coding 423 amino acids. BLAST analysis showed that there were only 23 nuoleotides in difference between this fragment and pomine GHRH receptor gene, and its homology was 98%. However, both GHRH receptor genes were constituted by 423 amino acids with the sequence homology of 96%. [ Conclusion] This study provides theoretical basis for further studies on the dwarf mechanism of Wuzhishan miniature pig.展开更多
目的了解咸阳市食品中单增李斯特菌的污染状况及分子流行病学特征。方法2010—2019年采集咸阳市12类1699份食品及酱制品加工环节样本,依据《国家食品安全风险监测工作手册》进行单增李斯特菌分离鉴定,用脉冲场凝胶电泳(pulsed field gel...目的了解咸阳市食品中单增李斯特菌的污染状况及分子流行病学特征。方法2010—2019年采集咸阳市12类1699份食品及酱制品加工环节样本,依据《国家食品安全风险监测工作手册》进行单增李斯特菌分离鉴定,用脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)进行分子分型,检测菌株血清表型,对菌株进行全基因组测序,分析其谱系、克隆群、序列型和血清群,采用核心基因组多位点序列分型方法(cgMLST)进行分子分型。结果1699份样本中检出单增李斯特菌72株,总检出率为4.24%,检出率最高的是生肉制品18.49%(22/119);1/2a、1/2b和1/2c为优势血清型(87.50%,63/72);分离株共分为40个PFGE带型,其中有3个优势带型(GX6A16.XY0009、GX6A16.XY0004、GX6A16.XY0003),初步建立了咸阳市单增李斯特菌的PFGE指纹图谱库;全基因组测序菌株分属3个谱系,以谱系II为主56.94%(41/72);血清群以Ⅱa为主,共31株(43.06%,31/71);分为15个CC型,其中CC224、CC8、CC9和CC87为优势CC型(56.94%,41/72)。cgMLST能将不同谱系、血清群和CC型的菌株明显分开,分为18个亚群,与CC型基本保持一致。结论咸阳市流通食品中单增李斯特菌污染状况持续存在,并有交叉污染的可能。建立的PFGE指纹图谱库可为单增李斯特菌引起的食源性疾病的预警和暴发溯源提供支持,基于全基因组的cgMLST分型可用于食源性疾病暴发调查中菌株的溯源。展开更多
基金Supported by Natural Science Foundation of Hainan Province(30515)~~
文摘[Objective] cDNA of growth hormone releasing hormone （GHRH） receptor gene from Wuzhishan miniature pig was cloned and its sequence was also analyzed. [Method] Using genomic DNA extracted from porcine ear tissues of Wuzhishan miniature pig as the template, three pairs of primers were designed by the reported cDNA sequence of porcine GHRH, and cDNA was also amplified by RT-PCR. After being recovered and purified, PCR products were ligated to pMD18-T and then transformed into Escherichia coli DH5a. The transformation products were analyzed by PCR and double enzyme digestion to screen positive clones, and the positive clones were sequenced after identification in LB liquid medium. [ Result] cDNA of Wuzhishan miniature pig GHRH receptor gene was obtained successfully, and its length was 1 577 bp coding 423 amino acids. BLAST analysis showed that there were only 23 nuoleotides in difference between this fragment and pomine GHRH receptor gene, and its homology was 98%. However, both GHRH receptor genes were constituted by 423 amino acids with the sequence homology of 96%. [ Conclusion] This study provides theoretical basis for further studies on the dwarf mechanism of Wuzhishan miniature pig.
文摘目的了解咸阳市食品中单增李斯特菌的污染状况及分子流行病学特征。方法2010—2019年采集咸阳市12类1699份食品及酱制品加工环节样本,依据《国家食品安全风险监测工作手册》进行单增李斯特菌分离鉴定,用脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)进行分子分型,检测菌株血清表型,对菌株进行全基因组测序,分析其谱系、克隆群、序列型和血清群,采用核心基因组多位点序列分型方法(cgMLST)进行分子分型。结果1699份样本中检出单增李斯特菌72株,总检出率为4.24%,检出率最高的是生肉制品18.49%(22/119);1/2a、1/2b和1/2c为优势血清型(87.50%,63/72);分离株共分为40个PFGE带型,其中有3个优势带型(GX6A16.XY0009、GX6A16.XY0004、GX6A16.XY0003),初步建立了咸阳市单增李斯特菌的PFGE指纹图谱库;全基因组测序菌株分属3个谱系,以谱系II为主56.94%(41/72);血清群以Ⅱa为主,共31株(43.06%,31/71);分为15个CC型,其中CC224、CC8、CC9和CC87为优势CC型(56.94%,41/72)。cgMLST能将不同谱系、血清群和CC型的菌株明显分开,分为18个亚群,与CC型基本保持一致。结论咸阳市流通食品中单增李斯特菌污染状况持续存在,并有交叉污染的可能。建立的PFGE指纹图谱库可为单增李斯特菌引起的食源性疾病的预警和暴发溯源提供支持,基于全基因组的cgMLST分型可用于食源性疾病暴发调查中菌株的溯源。
