Background： Embryonic mortality during the period of implantation strongly affects litter size in pigs. Progesterone receptor（PGR） paracrine signaling has been recognized to play a significant role in embryonic imp...Background： Embryonic mortality during the period of implantation strongly affects litter size in pigs. Progesterone receptor（PGR） paracrine signaling has been recognized to play a significant role in embryonic implantation. IHH,NR2F2, BMP2, FKBP4 and HAND2 were proved to involve in PGR paracrine signaling. The objective of this study was to evaluate the expression of IHH, NR2F2, BMP2, FKBP4 and HAND2 in endometrium of pregnant sows and to further investigate these genes＇ effect on litter size in pigs. Real-time PCR, western blot and immunostaining were used to study target genes/proteins expression in endometrium in pigs. RFLP-PCR was used to detect single nucleotide polymorphisms（SNPs） of target genes.Results： The results showed that the m RNA and protein expression levels of IHH, NR2F2 and BMP2 were up-regulated during implantation period（P 〈 0.05 or P 〈 0.01）. All target proteins were mainly observed in luminal epithelium and glandular epithelium. Interestingly, the staining of NR2F2 and HAND2 was also strong in stroma. SNPs detection revealed that there was a-204 C 〉 A mutation in promoter region of NR2F2 gene. Three genotypes were found in Large White, Landrace and Duroc sows. A total of 1847 litter records from 625 sows genotyped at NR2F2 gene were used to analyze the total number born（TNB） and number born alive（NBA）. The study of the effect on litter size suggested that sows with genotype CC tend to have higher litter size.Conclusions： These results showed the expression patterns of genes/proteins involved in PGR paracrine signaling over implantation time. And the candidate gene for litter size was identified from genes involved in this signaling. This study could be a resource for further studies to identify the roles of these genes for embryonic implantation in pigs.展开更多
The matrix metalloproteinase 23 （MMP-23）, which might play a role in ovulation in mammals, was one of the promising candidate genes for litter size traits in pigs. In the present research, partial sequence of porcin...The matrix metalloproteinase 23 （MMP-23）, which might play a role in ovulation in mammals, was one of the promising candidate genes for litter size traits in pigs. In the present research, partial sequence of porcine MMP-23 （pMMP-23） gene, including exons 2-8 （GenBank： EU360790）, was obtained. Real-time PCR analysis revealed that pMMP-23 gene was highly expressed in ovary. PCR-Sau3A I-RFLP and PCR-Acc II-RFLP assay were established to detect a C/T mutation in exon 3 （EU360790： g. 269C〉T） and an A/G mutation in exon 4 （EU360790： g. 505A〉G）, respectively. Association study for these two SNPs with litter size was assessed in three independent populations （Minzhu, Landrace I and Landrace II）. Statistical analysis demonstrated that for second and subsequent litters, TT sows produced more TNB than CC pigs in Landrace breed （P〈0.05） at g. 269C〉T locus, and the additive effect was significant （P〈0.05）; GG sows produced more TNB and NBA than AA pigs in Minzhu （P〈0.01） and Landrace breeds （P〈0.05） at g. 505A〉G locus, and the additive effect was significant （P〈0.01 or P〈0.05）. Our study suggested that the pMMP-23 gene might be a novel candidate gene for litter size traits, and g. 505A〉G locus might be a useful molecular marker for marker assisted selection （MAS）.展开更多
基金supported by National Natural Science Foundation of China (No.31172176)China Agriculture Research System (No. CARS-36)Program for Changjiang Scholar and Innovation Research Team in University (IRT1191)
文摘Background： Embryonic mortality during the period of implantation strongly affects litter size in pigs. Progesterone receptor（PGR） paracrine signaling has been recognized to play a significant role in embryonic implantation. IHH,NR2F2, BMP2, FKBP4 and HAND2 were proved to involve in PGR paracrine signaling. The objective of this study was to evaluate the expression of IHH, NR2F2, BMP2, FKBP4 and HAND2 in endometrium of pregnant sows and to further investigate these genes＇ effect on litter size in pigs. Real-time PCR, western blot and immunostaining were used to study target genes/proteins expression in endometrium in pigs. RFLP-PCR was used to detect single nucleotide polymorphisms（SNPs） of target genes.Results： The results showed that the m RNA and protein expression levels of IHH, NR2F2 and BMP2 were up-regulated during implantation period（P 〈 0.05 or P 〈 0.01）. All target proteins were mainly observed in luminal epithelium and glandular epithelium. Interestingly, the staining of NR2F2 and HAND2 was also strong in stroma. SNPs detection revealed that there was a-204 C 〉 A mutation in promoter region of NR2F2 gene. Three genotypes were found in Large White, Landrace and Duroc sows. A total of 1847 litter records from 625 sows genotyped at NR2F2 gene were used to analyze the total number born（TNB） and number born alive（NBA）. The study of the effect on litter size suggested that sows with genotype CC tend to have higher litter size.Conclusions： These results showed the expression patterns of genes/proteins involved in PGR paracrine signaling over implantation time. And the candidate gene for litter size was identified from genes involved in this signaling. This study could be a resource for further studies to identify the roles of these genes for embryonic implantation in pigs.
基金supported by the Educational Commission of Heilongjiang Province, China (11541031)
文摘The matrix metalloproteinase 23 （MMP-23）, which might play a role in ovulation in mammals, was one of the promising candidate genes for litter size traits in pigs. In the present research, partial sequence of porcine MMP-23 （pMMP-23） gene, including exons 2-8 （GenBank： EU360790）, was obtained. Real-time PCR analysis revealed that pMMP-23 gene was highly expressed in ovary. PCR-Sau3A I-RFLP and PCR-Acc II-RFLP assay were established to detect a C/T mutation in exon 3 （EU360790： g. 269C〉T） and an A/G mutation in exon 4 （EU360790： g. 505A〉G）, respectively. Association study for these two SNPs with litter size was assessed in three independent populations （Minzhu, Landrace I and Landrace II）. Statistical analysis demonstrated that for second and subsequent litters, TT sows produced more TNB than CC pigs in Landrace breed （P〈0.05） at g. 269C〉T locus, and the additive effect was significant （P〈0.05）; GG sows produced more TNB and NBA than AA pigs in Minzhu （P〈0.01） and Landrace breeds （P〈0.05） at g. 505A〉G locus, and the additive effect was significant （P〈0.01 or P〈0.05）. Our study suggested that the pMMP-23 gene might be a novel candidate gene for litter size traits, and g. 505A〉G locus might be a useful molecular marker for marker assisted selection （MAS）.
文摘【目的】绵羊产羔数是一个极其复杂的性状,受诸多因素影响。绵羊排卵数是最重要的因素之一,而SMAD蛋白在哺乳动物卵泡发育和颗粒细胞生长分化过程中发挥着重要作用。因此本文基于前期绵羊基因组重测序数据,深入研究SMAD家族成员1 (SMAD family member 1, SMAD1)基因在不同繁殖力小尾寒羊组织表达模式,并探讨其多态性与绵羊产羔数的关系,以揭示其影响产羔数的机制,为绵羊分子育种提供科学依据。【方法】首先,采用反转录PCR技术检测SMAD1基因在不同繁殖力小尾寒羊群体大脑,小脑,下丘脑,垂体,子宫,卵巢,输卵管,心脏,肝脏,脾脏,肺脏,肾脏,肾上腺,甲状腺,大肠,小肠,胰腺,瘤胃,肾脂19种组织的表达模式,然后利用实时荧光定量PCR技术检测SMAD1基因在不同繁殖力小尾寒羊下丘脑,垂体,子宫,卵巢,输卵管5种繁殖组织的相对表达量。随后采用Sequenom MassARRAY?SNP技术对SMAD1基因5个单核苷酸多态性(singlenucleotide polymorphism, SNP)位点在小尾寒羊(n=380)、湖羊(n=101)、苏尼特羊(n=21)、草原型藏羊(n=161)、策勒黑羊(n=52)、滩羊(n=22)6个绵羊品种中进行基因型检测,计算其群体遗传学指标,利用SPSS19.0软件分析5个SNPs与小尾寒羊产羔数的相关性。【结果】PCR结果显示,SMAD1基因在不同繁殖力小尾寒羊全身性组织均有表达,在小尾寒羊单羔群体卵巢的表达量极显著高于多羔群体(P<0.01),小尾寒羊单羔群体下丘脑、垂体的表达量显著高于多羔群体(P<0.05);基因分型结果表明,g.12485895A>G,g.12487558G>A和g.12487190G>T位点在单、多羔绵羊品种中基因型和等位基因频率均差异显著(P<0.05);而g.12508874T>C和g.12487467A>G位点在单、多羔绵羊品种中基因型和等位基因频率均差异不显著(P>0.05);群体遗传学分析表明,g.12485895A>G、g.12487558G>A、g.12508874T>C、g.12487467A>G、g.12487190G>T位点在小尾寒羊、湖羊、策勒黑羊、苏尼特羊、草原型藏羊中均为中度多态(0.25<PIC<0.5),g.12508874T>C位点在滩羊群体表现为低度多态(PIC<0.25);卡方适合性检验表明,g.12485895A>G和g.12487467A>G位点在小尾寒羊和草原型藏羊中处在Hardy-Weinberg不平衡状态(P<0.05),g.12487558G>A在小尾寒羊和湖羊群体处于Hardy-Weinberg不平衡状态(P<0.05),g.12487190G>T位点在草原型藏羊处于Hardy-Weinberg不平衡状态(P<0.05)。其他位点在6个绵羊品种中均处在Hardy-Weinberg平衡状态(P>0.05);关联分析表明,g.12485895A>G,g.12487558G>A,g.12508874T>C和g.12487467A>G位点与小尾寒羊产羔数无显著关联。g.12487190G>T位点TT基因型母羊前三胎的产羔数均显著高于GT和GG基因型母羊(P<0.05)。将该位点与小尾寒羊FecB(A746G)不同基因型进行组合后发现,AA-GG、AA-GT、AA-TT型母羊产羔数显著低于其他组合基因型母羊(P<0.05)。【结论】SMAD1与小尾寒羊繁殖密切相关,g.12487190G>T可作为小尾寒羊产羔性状选育的潜在分子标记。
