PCR-SSCP Analysis Of BMPR-Ⅰ B And Differential Expression Of Prolificacy Gene In Goat

The prolificacy of goat belongs to productive traits with low heritability, which is difficult to be improved only by conventional breeding methods, but molecular marker should accelerate the choice progress of productive traits. At present, the researches of molecular level in goat fecundity mainly concentrate on the candidate genes, in which the bone morphogenetic protein receptor gene (BMPR-â… B) is the fist major-gene that was found in sheep. The mutation in the highly conserved intracellular kinase signaling domain of BMPR-â… B is associated with the high fecundity of Booroola sheep entirely. In order to detect whether such mutation exist in the native goat population in central area of Hebei Province, 140bp fragment containing the site 746 was amplified with particular primers. SSCP was used to detect the polymorphism of this site among the native goat herd with different fecundity(high- fecundity group 22, low- fecundity group 23, general group 78). The results showed that, there is no A746G mutation in this native goat population, which indicated that the mutation in BMPR-â… B (A746G) associated with the high fecundity of Booroola sheep has no effect on the prolificacy of native goat.In order to find new gene or EST sequence which is associated with prolificacy in goat, 12 goats were selected from the native goat population and divided into 2 groups according to their reproductive records. Differential display reverse transcript PCR (DDRT-PCR) method was used in the analysis of the discrepancy of gene expression in ovarian tissue of goats in estrum period. 30 differential segments were obtained via polyacrylamide gel electrophoresis, in which 12 segments were obtained by second PCR amplification; 4 differential segments were finally obtained via reverse Northern blot, and these fragments differentially expressed in quantity. After sequencing by cloning, semi-quantitative PCR measure was used to verify the result again. These segments were submitted into Genbank, and aligned with reported sequences in NCBI. One of the 4 segments was 94% similar to the mRNA of PCNP gene in cattle, which indicated that it may be a homolog of PCNP gene. Complete CDS sequences and amino acid sequences of the PCNP gene of 8 species including cattle, human, mouse were analyzed with the method of comparative genomics and bioinformatics. The chemicophysical properties and second structure of the amino acid sequences which were coded by PCNP gene were predicted by online analysis softwares, which include ProtParam, SCOPMA, SMART. Results showed that nucleic acid sequence and amino acid sequence of PCNP gene are conservative, and the PCNP protein may be extrapolated to be an unstable hydrophilic nucleoprotein, and involved in cell proliferation regulation. Another fragment is shared 81% with one clone segment (THY010003E05) of wild pig (Sus scrofa), but without known function. The other two were new expressed segments, so highly homologous sequences were not found in NCBI.