Isolation, sequence identification and tissue expression distribution of three novel porcine genes--RAB14, S35A3 and ITM2A.

The complete coding sequences of three porcine genes--RAB14, S35A3 and ITM2A were amplified using the reverse transcriptase polymerase chain reaction (RT-PCR) based on the conserved sequence information of the mouse or other mammals. The nucleotide sequence analysis of these three genes revealed that porcine RAB14 gene encodes a protein of 215 amino acids that contains the conserved putative Ras-related protein Rab-14 domain and has high homology with the Ras-related protein Rab-14 (RAB14) of four species--human and mouse (99%) and rat (100%), dictyostelium discoideum (71%). The porcine S35A3 gene encodes a protein of 325 amino acids that contains the conserved putative nucleotide-sugar transporter domain and has high homology with the UDP-N-acetylglucosamine transporter (S35A3) of five species--cattle (98%), dog (97%), human (96%), mouse (95%) and rat (94%). The porcine ITM2A gene encodes a protein of 254 amino acids that contains the conserved putative BRICHOS domain and has high homology with the integral membrane protein 2A (ITM2A) of two species--human (89%), and mouse (88%). The tissue expression analysis indicated that the swine RAB14 gene was over-expressed in fat, lung, spleen, and kidney, moderately in large intestine, weakly in small intestine, and hardly expressed in muscle and liver. The swine S35A3 gene was moderately expressed in large intestine, fat, and spleen, weakly in liver and lung, and almost not expressed in muscle, small intestine, and liver. The swine ITM2A gene was over-expressed in fat and spleen, moderately in lung, weakly in muscle, and hardly expressed in liver, small intestine, large intestine, and kidney. Our experiment established the primary foundation for further research on these three swine genes.