【摘要】 目的探讨肝受体类似物-1（liver receptor homolog-1,Lrh-1;NR5A2）基因序列差异与小鼠排卵数性状间关系。方法根据GenBank中NM₀01159769序列设计了5对引物扩增Lrh-1基因CDS区,用单链构象多态性（Single-strand conformation polymorphism,SSCP）分析小鼠Lrh-1基因序列差异,分析Lrh-1基因与小鼠排卵数间关系。结果①在5对引物中只有引物P2和P5扩增产物存在多态性,引物P2扩增产物存在两种基因型AA和AB型,其中AB型发生（C674A）突变,这种突变导致编码的140位氨基酸由谷氨酰胺变为赖氨酸。②引物P5扩增产物存在三种多态类型SSCP-1、SSCP-2和SSCP-3,SSCP-1和SSCP-3型核酸序列比SSCP-2型少25个碱基,SSCP-3型除缺失区段外,其他区域碱基序列与SSCP-2型有5处碱基突变,而与SSCP-1型核酸序列有34处碱基差异,经BLAST分析,SSCP-2型与NM₀01159769序列相似,SSCP-1型与NM₀01159769序列相差较多,而与NG₀12313.1序列相似,通过氨基酸序列比对分析,SSCP-3型1652处的A→G的突变导致氨基酸由丙氨酸变为苏氨酸,1678位G→C的突变使原密码子TAC（酪氨酸Y）变为TAG（终止子）。③引物P2 AA型（27.27±8.52）与AB型小鼠的平均排卵数（25.92±11.73）间差异无显著性（P>0.05）;引物P5 SSCP-2型平均排卵数（35.00±14.58）显著高于SS-CP-3型平均排卵数（19.50±7.94）（P<0.05）,SSCP-1型（26.2±8.18）与SSCP-2型、SSCP-3型平均排卵数间差异无显著性（P>0.05）。结论明确了Lrh-1基因序列差异与小鼠排卵数性状间关系,为深入研究Lrh-1基因对动物生殖调控机理提供依据。更多还原

【Abstract】 Objective To explore the correlation of liver receptor homolog-1（Lrh-1;NR5A2） gene nucleotide sequence and ovulation number in mice.Methods Five primers were designed according to the sequence of NM₀01159769 and amplified the coding sequence of Lrh-1 gene.Single-strand conformation polymorphism was used to analyze the correlation of difference in Lrh-1 nucleotide sequence and ovulation number.Results（1） There were polymorphisms in P2 and P5 PCR products.The P2 PCR products had two genotypes: AA and AB.The AB genotype had one base mutation of C674A,and the mutation led to amino acid change of Q140K.（2） The P5 PCR products had three SSCP-types: SSCP-1,SSCP-2 and SSCP-3.The nucleotide sequences of SSCP-1 and SSCP-3 had 25 base deletion than SSCP-2 type.Five base mutations between SSCP-3 and SSCP-2,34 base mutations between SSCP-3 and SSCP-1 were found.When BLAST in NCBI,the nucleotide sequence of SSCP-2 was like NM₀01159769,but SSCP-1 sequence was like NG₀12313.1.The base mutation of A1652G caused alanine changed to threonine and the base mutation of G1678C caused tyrosine changed to termination codon in peptide chain of SSCP-3 type.（3）There was no significant difference of average ovulation numbers between AA genotype（27.27±8.52） and AB genotype（25.92±11.73） in P2 PCR products（P>0.05）.In P5 PCR products,the SSCP-2 type（35.00±14.58） had a significantly higher average ovulation number than SSCP-3 type’s（19.50±7.94）（P<0.05）.Conclusions Definite correlations of Lrh-1 gene and ovulation number have been established in mice.The results will contribute to the research of Lrh-1 gene molecular mechanism and regulatory pathway in animal reproduction.更多还原