Putative Krüppel target gene of novel sequence expressed in Drosophila VO5 muscle precursors

Krüppel (Kr), a member of the gap class of Drosophila segmentation genes, encodes a zinc finger-type transcription factor. After blastoderm formation, Kr is expressed in various spatially and temporally restricted patterns of the developing embryo, including a subset of muscle precursors. By virtue of Krüppel in vitro binding sites, we identified a putative Kr target gene, termed KrT95D. It encodes a novel protein which contains evolutionarily conserved regions. KrT95D is expressed in spatially restricted patterns throughout embryogenesis. Kr and KrT95D expression overlap in several locations including muscle precursor cells, the tip cell of the Malpighian tubules and the ventral midline cells of the central nervous system. Results from the analysis of the KrT95D expression pattern in Kr loss-of-fuction and Kr gain-of-function embryos suggest that Kr activity is not essential for KrT95D expression in most locations of the embryo, except in the muscle precursors VO5.