Abstract
We have analysed the expression, during embryogenesis, of a Drosophila gene asrij (Sanskrit; asR ij = blood), which encodes a novel conserved protein with putative transmembrane domains. asrij is expressed in the pole cells, amnioserosa, trachea and hemocytes. Embryos homozygous for a chromosomal deficiency that removes asrij have no embryonic hemocytes. Expression in the blood-cell lineage precedes that of known hematopoietic transcription factors. These results suggest that Drosophila asrij functions in the hematopoietic lineage.
