How affinity of the ELT-2 GATA factor binding to acting regulatory sites controls intestinal gene transcription.

We define a quantitative relationship between the affinity with which the intestine-specific GATA factor ELT-2 binds to -acting regulatory motifs and the resulting transcription of , a target gene representative of genes involved in intestine differentiation. By establishing an experimental system that allows unknown parameters (e.g.

A 44 bp intestine-specific hermaphrodite-specific enhancer from the C. elegans vit-2 vitellogenin gene is directly regulated by ELT-2, MAB-3, FKH-9 and DAF-16 and indirectly regulated by the germline, by daf-2/insulin signaling and by the TGF-β/Sma/Mab pathway.

The Caenorhabditis elegans vitellogenin genes are transcribed in the intestine of adult hermaphrodites but not of males. A 44-bp region from the vit-2 gene promoter is able largely to reconstitute this tissue-, stage- and sex-specific-expression. This "enhancer" contains a binding site for the DM-domain factor MAB-3, the male-specific repressor of vitellogenesis, as well as an activator site that we show is the direct target of the intestinal GATA factor ELT-2.