Study Of Biological Function On A Novel Gene, OCIAD2 Of Liaoning Cashmere Goat

Liaoning cashmere goat is China’s unique genetic species and its yield of cashmere production is first in China, it is hailed as “national treasure” and is a protected species of animal genes.The cashmere which is producted by Liaoning cashmere goat is superior animal fiber textile material and has very important economic value.In previous work, we constructed a skin cDNA library of Liaoning cashmere goat and isolated a full-length cDNA clone termed OCIAD2(Ovarian cancer immuno-reactive antigen domain-containing protein 2). Firstly, we analyzed the cDNA and amino acid sequences of OCIAD2, and analyzed physico-chemical properties, hydrophobicity, transmembrane domain, phosphorylation site,conserved domain,forecasted secondary structure, signal peptide, located subcelluar fraction and established evolutionary tree by biological informatics analysis. Then we used RT-PCR to detect the expression of OCIAD2 gene in all internal organs, situ hybridization was used to detected specificity expression sites of OCIAD2 gene, the contents of OCIAD2 gene expression in the primary and secondary hair follicles during different growth periods was detected by Real-time RT-PCR. Otherwise, we detected the effect on OCIAD2 after interfering the expression of Noggin gene.The results were as follow:(1) The biological informatics analysis results showed that it could encode the protein which included 154 amino acids and was hydrophilic; the protein’s secondary structure had a high proportion of random coil structure(68.18%); the protein was a two transmembrane protein, contained a conservative protein structure domain, had two transmembrane regions, lacked of signal peptide and was most likely to locate in the nucleus. OCIAD2 gene of Liaoning cashmere goat and the sheep in home has higher homology.(2) RT-PCR detection showed that OCIAD2 gene was dramatically expressed in heart, kidney and spleen, was lightly expressed in skin and was hardly expressed in liver and lungs.(3) In situ hybridization showed that OCIAD2 gene was obviously expressed in internal root sheath of the primary and secondary hair follicles, was lightly expressed in stromal cells around the hair follicles and was not expressed in hair shaft, external root sheath and hair follicle mastoi.(4) Real-time PCR results showed that the expression of OCIAD2 in second hair follicles was 3.89 times(P<0.01) of the primary follicles during anagen; the expression of OCIAD2 in the primary hair follicles was 1.22 times(P<0.01) of the second follicles during catagen.(5) After interfering the expression of Noggin gene, the relative expression level of OCIAD2 gene showed an upward trend, it is beneficial to improve the the cashmere quality of cashmere goat.By the above results, we can draw the following conclusions:(1) By biological informatics analysis, Real-time PCR, situ hybridization and so on, we deduced that OCIAD2 might impact cashmere of Liaoning cashmere goat to some extent.(2) Interference Noggin gene expression can promote OCIAD2 gene expression. These findings provide important experimental evidence for researching subsequently the effect of OCIAD2 gene on Liaoning chashmere goat.