First Author | Seino Y | Year | 2008 |
Journal | J Biol Chem | Volume | 283 |
Issue | 8 | Pages | 4905-11 |
PubMed ID | 18093975 | Mgi Jnum | J:132176 |
Mgi Id | MGI:3775349 | Doi | 10.1074/jbc.M707928200 |
Citation | Seino Y, et al. (2008) Isx participates in the maintenance of vitamin A metabolism by regulation of beta-carotene 15,15'-monooxygenase (Bcmo1) expression. J Biol Chem 283(8):4905-11 |
abstractText | Isx (intestine specific homeobox) is an intestine-specific transcription factor. To elucidate its physiological function, we generated Isx-deficient mice by knocking in the beta-galactosidase gene (LacZ) in the Isx locus (IsxLacZ/LacZ mice). LacZ staining of heterozygous (IsxLacZ/+) mice revealed that Isx was expressed abundantly in intestinal epithelial cells from duodenum to proximal colon. Quantitative mRNA expression profiling of duodenum and jejunum showed that beta-carotene 15,15'-monooxygenase (EC1.14.99.36 Bcmo1) and the class B type I scavenger receptor, which are involved in vitamin A synthesis and carotenoid uptake, respectively, were drastically increased in IsxLacZ/LacZ mice. Although mild vitamin A deficiency decreased Isx expression in duodenum of wild-type (Isx+/+) mice, severe vitamin A deficiency decreased Isx mRNA expression in both duodenum and jejunum of Isx+/+ mice. On the other hand, vitamin A deficiency increased Bcmo1 expression in both duodenum and jejunum of Isx+/+ mice. However, Bcmo1 expression was not increased in duodenum of IsxLacZ/LacZ mice by mild vitamin A deficiency. These data suggest that Isx participates in the maintenance of vitamin A metabolism by regulating Bcmo1 expression in the intestine. |