Developmental changes of the expression of the genes regulated by retinoic acid in the small intestine of rats.
Retinoic acid (RA) serves as a hormone-like nutrient and it plays pivotal roles in cellular differentiation and proliferation in various tissues including the small intestine. In this study, we aimed to explore a possible role of RA signaling in the developing rat small intestine of perinatal (embryonic and newborn) and suckling-weaning transition period, and we investigated the changes in the expression of several genes regulated by RA. Northern blot analysis showed that both retinal dehydrogenase 1 (RALDH1) and retinal dehydrogenase 2 (RALDH2) mRNA levels were higher in 19-day fetal (2 days before birth) small intestine and then declined after birth. Retinoid X receptor alpha (RXRalpha) mRNA and retinoic acid receptor alpha (RARalpha) mRNA levels in the small intestine showed high levels in perinatal period compared with suckling-weaning transition period. RA-target genes such as retinoic acid receptor beta (RARbeta) and cellular retinol-binding protein, type II (CRBPII) mRNA levels were significantly increased in the perinatal small intestine. Furthermore, mRNA levels of hepatocyte nuclear factor-4 (HNF-4), which is one of the possible RA-target gene and a transcription factor regulating CRBPII gene expression, was also increased in the perinatal small intestine. These results suggest that the possible perinatal RA production by RALDHs might regulate various RA-target genes including CRBPII and RARalpha through RXRalpha or HNF-4 in the small intestine.
Ogura
Yuko
Y
Laboratory of Nutritional Physiology and COE Program in the 21st Century, University of Shizuoka School of Food and Nutritional Sciences, 52-1 Yada, Shizuoka-shi 422-8526, Japan.
Suruga
Kazuhito
K
Takase
Sachiko
S
Goda
Toshinao
T
D000445:Aldehyde Oxidoreductases / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D017931:DNA Primers; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D051557:Hepatocyte Nuclear Factor 4 / Q000378:metabolism; D007421:Intestine, Small / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018168:Receptors, Retinoic Acid / Q000378:metabolism; D000072482:Retinoic Acid Receptor alpha; D047490:Retinoid X Receptor alpha / Q000378:metabolism; D012177:Retinol-Binding Proteins / Q000378:metabolism; D054840:Retinol-Binding Proteins, Cellular; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014212:Tretinoin / Q000494:pharmacology*
D017931:DNA Primers; D051557:Hepatocyte Nuclear Factor 4; C000607073:Rara protein, rat; C518461:Rbp2 protein, rat; D018168:Receptors, Retinoic Acid; D000072482:Retinoic Acid Receptor alpha; D047490:Retinoid X Receptor alpha; D012177:Retinol-Binding Proteins; D054840:Retinol-Binding Proteins, Cellular; C082925:retinoic acid receptor beta; D014212:Tretinoin; D000445:Aldehyde Oxidoreductases