Interaction of the non-protein-coding developmental and stress-inducible hsrω gene with Ras genes of Drosophila melanogaster

Abstract

The 93D or hsrω (hsr-omega) is an unusual non-protein-coding gene which shows a dynamic developmental expression in most cell types ofDrosophila melanogaster and which, besides being a member of the heat shock gene family, is uniquely induced in polytene cells by a variety of amides. We briefly review the various aspects of this gene's organization, regulation and inducible properties and present our recent data to show that, similar to our earlier report of interaction between the hsrω and hsp83 genes, mutations at the Ras1 or the Ras3 gene of D. melanogaster also dominatly enhance the pre-pupal and pupal lethality of embryos that are nullosomic for this gene. In the absence of any protein product, the hsrω transcripts are suggested to interact with the Ras 1 signaling cascade. The interaction of a non-translatable, developmentally produced as well as heat and other stress inducible RNA with the Ras signaling proteins and with the Hsp83 chaperone protein opens new possibilities for understanding of functions of this intriguing gene.