Overexpression of TDRP1 gene in swine testis cell and its global transcriptome analysis

The testis development-related protein-1 (TDRP1) gene was first isolated in spermatogenic cells of testis, and was related to the spermatogenesis and reproduction traits in mammals. This study was performed to further analyze the function of the pig TDRP1 gene by microarray screening of the TDRP1-overexpressed swine testis (ST) cell. After transfection of the recombinant pcDNA3.1-TDRP1 vector into the ST cell, the expression of the TDRP1 gene continued to increase at 12, 24, and 36 h post-transfection, and then decreased at 48 h, as indicated by both the fluorescence signal and quantitative PCR. Microarray screening revealed 529 upregulated and 1086 downregulated genes in TDRP1-overexpressed ST cells at 24 h post-transfection (TD-24) versus untransfected control (TD-blank), and 764 upregulated and 858 downregulated genes at 36 h post-transfection (TD-36) versus TD-blank, as well as 720 upregulated and 375 downregulated genes in TD-36 versus TD-24. As far as three contrasts were totally considered, 29 common genes were identified, including 17 upregulated genes and 12 downregulated ones. Further, Kyoto encyclopedia of genes and genomes prediction analysis indicated that some of these 29 differently expressed genes were involved in a number of biological pathways. Among the 17 upregulated genes, the PMAIP1 gene was significantly enriched in the p53 signaling pathway, and the others were the DDIT3 gene in the mitogen-activated protein kinases (MAPK) signaling pathway, the PPP1R3C gene in the insulin signaling pathway, as well as the GADD45A gene in the p53 signaling pathway, MAPK signaling pathway, and the cell cycle. Among the 12 downregulated genes, the SFRP4 gene was significantly enriched in the Wnt signaling pathway. This study indicated that the TDRP1 gene regulated PMAIP1, GADD45A, DDIT3, and PPP1R3C expression, and these genes involving p53, MAPK, insulin, and Wnt signaling pathways are related to spermatogenesis or reproduction in pig.