摘要
采用RT-PCR技术,从香猪的肝脏总RNA中克隆了3个对氧磷酯酶(paraoxonase,PON)基因:PON1、PON2、PON3,其cDNA分别长1164、1212和1080bp,各包含1个完整的开放阅读框,分别编码355、354、354个氨基酸组成的前体,其N-端的15、23、23个氨基酸为信号肽。香猪PON1基因中有1个碱基变异,不改变编码的氨基酸,为无义突变;香猪PON2基因中有2个碱基改变,导致成熟肽发生Q234R、V269I替换;香猪PON3基因中有1个碱基变化,使成熟肽出现R127H替换。经三维结构预测分析,这3个氨基酸位点的变化将影响蛋白质内部区域的微环境,影响对氧磷酯酶的功能,可能与香猪的抗逆性有一定的联系。
Three genes of paraoxonase （PON） family were separated from the liver of Xiang pig by reverse transcription polymerase chain reaction （RT-PCR） method. The cDNA of PON1, PON2 and PON3 were 1164, 1212 and 1080 base pairs in length, respectively. All of them contained complete open reading frame （ORF） coding for three precursors. The signal pep- tides were predicted to be 15 amino acids （aa） in PON1, 23 aa in PON2 and 23 aa in PON3 at the N-terminus of precursors. A nonsense mutation was found out from PON1 gene. Two changes in PON2 gene resulted in substitution from glutamine to ar- ginine at 234 site （Q234R） and valine to isoleucine at 269 site （V269I） in the matured PON2 protein. In PON3, only one mu- tation lead to substitution from arginine to histidine at 127 site （R127H） of the matured protein. All of the three replacements in mature proteins might change the microenvironment in the internal proteins based on the prediction of the three dimension structures of the matured proteins online. It suggested that the differences of the three paraoxonase genes might correlate to the stress resistance of Xiang pig.
出处
《中国畜牧兽医》
CAS
北大核心
2012年第7期15-19,共5页
China Animal Husbandry & Veterinary Medicine
基金
贵州省培育项目(黔教科2007-001)
贵州省自然科学基金(黔科合J字[2008]2129)
贵州省创新人才团队专项(黔科合人才团队2009-4006)
