RETINOIC ACID INDUCTION OF MOUSE CELLULAR RETINOIC ACID-BINDING PROTEIN-I GENE-EXPRESSION IS ENHANCED BY SPHINGANINE

Cellular retinoic acid-binding protein-I (CRABP-I) gene expression is induced in mouse embryonal carcinoma P19 cells specifically by retinoi c acid (RA) and the induction is enhanced by sphinganine. The effects of retinoic acid and sphinganine on CRABP-I gene expression can be acc ounted for by a stimulation of its transcription rate. Using a lacZ re porter system, it was determined that a DNA fragment containing a puta tive AP-1 binding site in the promoter region of CRABP-I gene is requi red for the up-regulation of CRABP-I gene transcription.