Molecular cloning and embryonic expression of dFKBP59, a novel Drosophila FK506-binding protein

A Drosophila cDNA encoding a structural homolog of mammalian FKBP59 (also i dentified as FKBP52), a member of the FK506-binding protein (FKBP) class of immunophilins, was isolated. The gene dFKBP59 corresponding to this cDNA h as been characterized and mapped to the 30D3-4 region. The predicted amino acid sequence of this cDNA shows that the dFKBP59 protein contains one high ly conserved FKBP12-like domain followed by two others with less conservati on. Northern hybridization reveals that the dFKBP59 mRNA is expressed throu ghout the Drosophila life-cycle. In contrast to its mammalian homologs, in situ hybridization detected dFKBP59 expression in specific tissues: the lym ph glands, Garland cells and oenocyte cells, which are all specialized tiss ues in which intensive exocytic/endocytic cycling takes place. Garland cell s and oenocytes (also called Drosophila nephrocytes) function in taking up waste material from the hemolymph. Finally, I have mapped an enhancer trap element within the 5' region of dFKBP59 which may help in future studies to address the question of its function during Drosophila development. (C) 20 00 Elsevier Science B.V. All rights reserved.