title: Differential gene expression in uterine endometrium during implantation in pigs.
abstract: Embryonic mortality during the implantation period strongly affects litter size in pigs. To analyze the differentially expressed genes (DEGs) in the endometrium during implantation and further to identify candidate genes for litter size, tissues of endometrial attachment sites and intersites were collected from nine pregnant sows on Days 13, 18, and 24 of pregnancy. Endometrium tissue was also collected from another three nonpregnant sows. Samples were hybridized to the porcine Agilent GeneChip microarray. The analysis of gene expression patterns over the implantation period revealed 858 DEGs at endometrial attachment sites. Comparisons of the gene files of attachment sites and intersites revealed 12, 51, and 89 DEGs on Days 13, 18, and 24 of pregnancy, respectively. Annotated function was used to identify overrepresented genetic processes, and several biological processes were considered as the most enriched. Genes related to vascular development, proteolysis, RNA metabolism and translation, protein modification, immune response, and hormone-related are discussed in detail. Then we combined microarray technology and linkage analysis to select powerful candidate genes for quantitative trait loci affecting pig litter size. Eighty-seven DEGs were located in quantitative trait loci related to litter size, that is, total number born and number born alive. Those candidate genes were thought to affect litter size by influencing embryonic implantation. Furthermore, single nucleotide polymorphism of VEGFA was shown to be associated with litter size in pigs. This study identified candidate genes for litter size that were related to embryonic implantation and could be a resource for target studies of genetic markers for litter size in pigs.
authors.affiliation: College of Animal Sciences and Technology, National Engineering Laboratory for Animal Breeding & Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, China Agricultural University, Beijing, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.affiliation: Ankang Yangchen Animal Husbandry Technology Co., Ltd., Ankang, China.
authors.forename: Aiyun
authors.initials: A
authors.lastname: Li
authors.affiliation: College of Animal Sciences and Technology, National Engineering Laboratory for Animal Breeding & Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, China Agricultural University, Beijing, China.
authors.forename: Wencheng
authors.initials: W
authors.lastname: Chen
authors.affiliation: College of Animal Sciences and Technology, National Engineering Laboratory for Animal Breeding & Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, China Agricultural University, Beijing, China.
authors.forename: Julong
authors.initials: J
authors.lastname: Wei
authors.affiliation: College of Animal Sciences and Technology, National Engineering Laboratory for Animal Breeding & Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, China Agricultural University, Beijing, China fujinlian@126.com.
authors.forename: Jinluan
authors.initials: J
authors.lastname: Fu
authors.affiliation: College of Animal Sciences and Technology, National Engineering Laboratory for Animal Breeding & Key Laboratory of Animal Genetics, Breeding and Reproduction, Ministry of Agriculture, China Agricultural University, Beijing, China agwang@cau.edu.cn.
authors.forename: Aiguo
authors.initials: A
authors.lastname: Wang
mesh_terms: D000818:Animals; D010064:Embryo Implantation / Q000235:genetics*; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000502:physiology*; D008098:Litter Size / Q000235:genetics; D011247:Pregnancy; D040641:Quantitative Trait Loci; D013552:Swine; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
chemical_list: D042461:Vascular Endothelial Growth Factor A
keywords: QTL; endometrium; gene expression; litter size; microarray