[A novel trans-regulatory locus in Drosophila].

A new trans-regulatory gene, leg-arista-wing complex (lawc), was earlier identified in a system of prolonged genetic instability induced by transpositions of structurally different mobile genetic elements, the P element and MDG Stalker. Mutations of this gene alter expression of many loci, including the achaete and scute proneural genes and the cut locus coding for a homeobox-containing protein. A product of lawc is involved in regulating expression of white. This role is played in cooperation with the product of Zeste which provides for a contact between the white promoter and enhancer. A possible role of the new locus in organogenesis, neurogenesis, and embryonic development is discussed on the basis of experimental findings.