Abstract
Jejunal expression of the genes for the vitamin A-binding protein CRBPII and the fatty acid-binding protein L-FABP is induced during the middle of the suckling period, whereas that of the genes for disaccharidase sucrase-isomaltase and the fructose transporter GLUT5 are induced from the middle to late suckling period. In this study, we demonstrated that induction of the CRBPII and L-FABP genes is mediated by one of the nuclear receptors, PPARα, whereas induction of the GLUT5 gene is regulated by the nuclear receptors for thyroid hormone (TRα-1) and glucocorticoid hormone (GR). Furthermore, we found that the signals of nutrients/hormones induce histone acetylation and binding of one of the chromatin remodeling factors, CBP/p300, to the upstream/transcriptional regions of these genes. Our results suggest that nutrients/hormones regulate the expression of jejunal genes, not only as activators of nucler transcriptional factors, but also as key factors for changing the remodeling of chromatin.
