Identification of the Porcine <i>G Protein-Coupled Receptor 41</i> and <i>43</i> Genes and Their Expression Pattern in Different Tissues and Development Stages

<div><p>Short-chain fatty acids (SCFAs) are not only an important energy source, but they also play a regulatory role in various physiological processes in humans and rodents. Current studies, mostly in humans and rodents, have revealed that SCFAs acted as endogenous ligands for <i>G protein-coupled receptor GPR41</i> and <i>GPR43</i>. Whether proteins similar to human <i>GPR41</i> and <i>GPR43</i> mediate the regulatory effects of SCFAs in swine remains unclear to date. The aims of this study were to determine whether <i>GPR41</i> and <i>GPR43</i> genes are expressed in porcine different tissues; and whether the expression of <i>GPR41</i> and <i>GPR43</i> is tissue-specific and/or time-associated. The alignment results showed that pig chromosome 6 contained GPR41 and GPR43 genes. Reverse transcription polymerase chain reaction (RT-PCR) indicated that GPR41 and GPR43 were expressed in porcine various tissues. The 2218 bp and 1908 bp nucleotide sequence representing the full-length <i>cDNA</i> sequence of porcine <i>GPR41</i> and <i>GPR43</i> was obtained from the ileum and spleen using rapid amplification of <i>cDNA</i> ends (RACE), which were capable of encoding 335 and 329 amino acid sequences, respectively. The structure prediction revealed that porcine <i>GPR41</i> and <i>GPR43</i> proteins had seven putative trans-membrane domains. The real-time PCR results indicated that <i>GPR41</i> and <i>GPR43</i> were expressed throughout the developmental stages in a tissue-specific and time-associated manner. <i>GPR41</i> and <i>GPR43</i> were most highly expressed in the ileum (<i>P</i><0.01) and the spleen (<i>P</i><0.01), respectively. Western blot results showed that porcine <i>GPR41</i> and <i>GPR43</i> proteins were expressed in a variety of porcine tissues, including the spleen, ileum, colon, and adipose tissue. In situ <i>GPR41</i> and <i>GPR43</i> immunoreactivities were observed through immunohistochemistry in the spleen, ileum, colon, and adipose tissue. In conclusion, the pig genome encoded <i>GPR41</i> and <i>GPR43</i> genes, and these two genes were detected in a variety of porcine tissues and expressed in tissue-specific and time-associated manner.</p>