HOMEODOMAIN BINDING-SITES IN THE 5' FLANKING REGION OF THE BOMBYX-MORI SILK FIBROIN LIGHT-CHAIN GENE

Multiple A + T-rich stretches in the 5′ flanking region of the Bombyx mori fibroin light-chain gene have been shown to bind two Drosophila homeodomain proteins, EVE (even-skipped) and ZEN (zerknüllt), with high affinities. Some of these sites fall into a class that has the established consensus sequence of the binding sites (TCAATTAAAT) for a diverse group of Drosophila homeodomain proteins, while others are quite heterogeneous except that they all possess a core TAAT motif. Since clusters of homeodomain binding sites can also be found in the promoters of other silk protein genes, the fibroin gene and the sericin-1 gene, these observations suggest a possible involvement of some homeobox genes in the regulation of a group of silk protein genes. © 1990 Academic Press Limited.