Figure 2.

Induction of E-MAP-115 expression by RA and no E-MAP-115 expression in ROSA63 mutant testis. (A) Time course of induction of βgeo* expression by RA in ROSA63 ES cells. Cells were serum-starved, and stimulated with RA for indicated time periods. Transcripts were detected by Northern blot analysis with a β-gal probe. Ethidium bromide staining of 28S ribosomal RNA is shown below as a loading control. (B) Southern blot analysis of DNAs from tail biopsies of wild-type (+/+), heterozygous (+/−), and homozygous (−/−) mutant mice with mixed probes of neo and wnt1. The intensity of the neo-positive band, absent in the wild type, is twice as high in the homozygote as in the heterozygote. The wnt1 genomic probe was used as an internal standard (i.s.). (C) Northern blot analysis of RNAs from wild-type (+/+), heterozygous (+/−), and homozygous (−/−) mutant testes with E-MAP-115 cDNA. The broadly expressed 3.4-kb and the testis-specific 2.5-kb transcripts were not detected in the homozygote. The positions of the 18S and 28S ribosomal RNAs are indicated on the left. (D) Time course of induction of endogenous E-MAP-115 expression by RA in wild-type ES cells. The experiment was performed as described in A with E-MAP-115 cDNA as a probe. (E) Induction of E-MAP-115 expression by retinol in the small intestine of VAD mice. RNAs from small intestines of VAD mice administered with or without retinol for 24 hr or 48 hr were probed with E-MAP-115 cDNA.