Interpretive Summary: Rapid Communication: Porcine CRTC3 gene clone, expression pattern, and its regulatory role in intestinal epithelial cells.
By: Surely Wallace
In an article published in July 2018 in the Journal of Animal Science, researchers characterized the tissue-specific expression and function of the CRTC3 gene in pigs.
In previous studies, CRTC3 has been shown to affect glucose and lipid metabolism, which may contribute to obesity. Knocking out the CRTC3 gene has been shown to be protective against obesity in mice. The authors’ aim was to study CRTC3 gene expression and function in pigs. Previous studies have looked at CRTC3 in mice and human cells, but not in pigs.
Six 60-day old pigs were sacrificed in this study. Tissue samples were collected from pig heart (HEA), liver (LIV), spleen (SPL), kidney (KID), small bowel (INT), muscle and adipose tissue (AAT). The full-length DNA of CRTC3 was cloned using the “3’-RACE” protocol described by Shan et al in 2009.
The cloned DNA sequence was compared to existing sequences in the BLAST database for human, mouse, horse, monkey, dog, rabbit and other select animal species. The authors determined that the porcine CRTC3 protein consisted of 620 amino acids. The amino acid sequence was reported to be most similar to humans (90.6%), followed by mouse (89%). Tissues from pig SPL and INT had the highest expression of CRTC3 (analysis by Western Blot and qPCR). High expression of CRTC3 proteins was also found in the cytoplasm of porcine IPEC-J2 intestinal epithelial cells. When the CRTC3 gene was knocked out, IPEC-J2 CRTC3 decreased, specifically in cells involved with intestinal epithelial tight junctions, which help maintain the gut barrier integrity. Specifically, zonula occludens-1, zonula occludens-2, occludin, and claudin-1 were significantly decreased (by 57.88%, 40.19%, 51.59% and 35.70%, respectively) when porcine CRTC3 was knocked out.
Overall, the data in this study suggests that there is justifiable need for more research into the function and expression of CRTC3 in pigs. It is possible that CRTC3 may influence not only adiposity, but also gut barrier, which suggests a potential role for CRTC3 in porcine nutrient absorption, inflammation, infection, and/or gut microbiota composition.
To view the full article, “Rapid Communication: Porcine CRTC3 gene clone, expression pattern, and its regulatory role in intestinal epithelial cells,” visit the Journal of Animal Science.