LEPR及LEP基因表达量对FecB不同基因型小尾寒羊产羔数的影响

摘要

The aim of this study was to determine if the expression of leptin receptor (LEPR) and leptin (LEP) genes was associated with litter size of Small Tail Han ewes.Twenty one healthy Small Tail Han ewes,composed of 9 FecB wild type (++) and 12 FecB mutation homozygous type (BB),about 2-3 years old,were used to investigate the ovulation rate by laparoscopy after spontaneous estrus with CIDR.Real-time PCR was used to detect the expression of LEPR and LEP genes in 11 tissues (heart,liver,spleen,lung,kidney,adrenal gland,fallopian tube,uterus,hypothalamus,pituitary and ovary)of Small Tail Han ewes during follicular phase and in hypothalamus-pituitary-ovary gonadal axis of Small Tail Han ewes (+ + and BB genotypes) during luteal phase and follicular phase.The results showed that both ovulation number (P=0.003 5) and litter size (P=0.004 0) of individuals with BB genotype were significantly higher than that of individuals with + + genotype.These 2 genes were all expressed in 11 tissues during follicular phase,the expression of LEPR gene was high in ovary,uterus and adrenal gland,and the expression of LEP gene was high in hypothalamus,pituitary,ovary and kidney.In ovary,the expression of LEPR gene of individuals with + + genotype during follicular phase was higher (P＞0.05) than that during luteal phase.The LEPR expression of individuals with BB genotype during follicular phase was significantly higher than that of individuals with + + genotype during follicular phase (P=0.007),BB genotype during luteal phase (P=0.003) and + + genotype during luteal phase (P =0.003).Therefore,we concluded that there was a positive correlation between the high expression of LEPR gene during follicular phase and high litter size in Small Tail Han ewes,which provided a new clue for improving litter size in Small Tail Han sheep.%旨在探索瘦素受体(Leptin receptor,LEPR)和瘦素(Leptin,LEP)基因与绵羊产羔数之间的关系.选择2～3岁健康母羊21只,对FecB野生纯合型(++)(9只)及突变纯合型(BB)(12只)小尾寒羊同期发情,通过腹腔镜记录排卵数.使用实时荧光定量PCR技术检测LEPR和LEP基因在卵泡期小尾寒羊11种组织(心、肝、脾、肺、肾、肾上腺、输卵管、子宫体、垂体、下丘脑、卵巢)中的表达以及在卵泡期和黄体期、BB型和++型小尾寒羊下丘脑垂体-卵巢性腺轴的表达.结果表明,BB型的排卵数(P=0.003 5)和产羔数(P=0.004 0)极显著高于++型.LEPR和LEP在卵泡期各个组织均有表达;其中LEPR基因在卵巢、子宫体、肾上腺组织高表达,LEP基因在下丘脑、垂体、卵巢和肾组织高表达.在卵巢中,卵泡期++型LEPR基因表达量高于黄体期++型,但差异不显著(P＞0.05);卵泡期BB型LEPR基因表达量极显著高于卵泡期++型(P=0.007)、黄体期BB型(P=0.003)和黄体期++型(P=0.003).综上表明,卵泡期LEPR基因高表达与小尾寒羊产羔数增加存在一定程度的正相关,这为小尾寒羊产羔性状选育提高提供了新的线索.