MRNA Expression Of PPP3CA And PPP6C Genes,Detection Of InDel And CNV And Their Associations With Important Economic Traits In Shaanbei White Cashmere Goats

Goat is one of the earliest domestic animals cultivated by human beings.In our country,local breeds are widely bred because of their early sexual maturity,strong adaptability,simple feeding and extensive management.Shaanbei white cashmere goat is an important cashmere and dual-purpose breed in China,it’s meat production rate and fecundity still needs to be improved.With the development of marker assisted selection,screening of key candidate genes with In Del and CNV has become a research hotspot.A recent genome-wide association analysis revealed that the PPP3 CA gene is an important candidate gene for goat fecundity and plays an important role in embryo implantation and development.As a member of the PPPs family,PPP6 C is mainly studied in cell meiosis and spermatogenesis.In this experiment,the m RNA expression characteristics of PPP3 CA and PPP6 C genes in the heart,liver,spleen,lung,kidney,muscle,ovary,fallopian tube,testis and other tissues of goats were first explored,and then mined the In Del and CNV loci of PPP3 CA and PPP6 C genes to analyze genetic parameters in a large population of Shaanbei white cashmere goats.Finally,the correlation between polymorphisms and reproductive traits and growth traits of873 goats was analyzed,in order to screen out key molecular markers and provide theoretical basis for subsequent breeding work.The main research results of the experiment are as follows:1.Study on the expression of PPP3 CA and PPP6 C genes in Shaanbei white cashmere goatsThis experiment explored the expression of PPP3 CA and PPP6 C genes in the heart,liver,spleen,lung,kidney,muscle,ovary,fallopian tube,testis and other tissues of adult Shaanbei white cashmere goats(6 males and females respectively).It was detected that PPP3 CA and PPP6 C genes were widely expressed in various tissues of goats.PPP3 CA gene was most highly expressed in lung,and highly expressed in fallopian tube of adult goat.PPP6 C gene was highly expressed in testis,and was also highly expressed in fallopian tube and ovary of adult goat.2.In Del and CNV detection of PPP3 CA and PPP6 C genes in Shaanbei white cashmere goatsBased on the high expression of PPP3 CA and PPP6 C genes in goat ovary,fallopian tube and testis,it further indicated that PPP3 CA and PPP6 C genes may be key candidate genes affecting goat fertility.This experiment screened and detected potential In Del and CNV locus in PPP3 CA and PPP6 C genes.A total of 9 potential In Del loci were screened,and the PPP3CA-P1,PPP3CA-P2,PPP3CA-P3 and PPP6C-P1 loci were found to be polymorphic by agarose gel electrophoresis and Sanger sequencing.The minimum allele frequencies of the four loci were 0.105,0.066,0.085,and 0.042,respectively,showing a low genetic diversity.In addition,according to the Animal Omics Database database,it was found that among the two genes,only the goat PPP3 CA gene had three CNV loci,and the three CNV loci in the PPP3 CA gene were identified,and all three loci were found to be polymorphic.3.Association analysis of PPP3 CA and PPP6 C genes In Del and CNV with economic traits in Shaanbei white cashmere goatsBased on the results of In Del and CNV detection of PPP3 CA and PPP6 C genes,the above mutation locus were further correlated with the large population of Shaanbei white cashmere goats.(n=873),and it was found that PPP3CA-P3 and PPP6C-P1 In Del locus can significantly affected litter size(P<0.01);PPP3CA-P1 locus significantly affected goat semen concentration(P<0.05);PPP3CA-P3 locus significantly affected goat body length;PPP6C-P1 locus significantly affected goat body height,hip cross height,chest depth and hip width(P < 0.05).Then,three CNV loci of PPP3 CA gene were identified by q PCR method,and the effect of CNV variation of this gene on reproductive and growth traits in353 Shaanbei white cashmere goats(female 307 and male 46 respectively).CNV1 and CNV2 loci were significantly associated with goat litter size,while CNV3 had no significant effect on litter size.CNV1 was significantly associated with ejaculate volume,semen concentration,sperm motility and viable sperm count,and CNV2 was significantly associated with semen concentration and viable sperm count.In conclusion,PPP3 CA and PPP6 C genes have abundant genetic polymorphisms and can be used for genetic selection of reproductive and growth traits in goats.