IDENTIFICATION OF A GENE FAMILY FROM DROSOPHILA-MELANOGASTER ENCODINGPROTEINS WITH HOMOLOGY TO INVERTEBRATE SARCOPLASMIC CALCIUM-BINDING PROTEINS (SCPS)

Using antibodies raised against the Drosophila Ca2+-binding protein DC ABP-23, we have isolated two distinct cDNA clones that encode Ca2+-bin ding proteins of the invertebrate sarcoplasmic calcium-binding protein (SCP) family, Southern blot analysis of whole genomic DNA has shown t hat one of the clones, Dcabp-A.1, is present in more than one copy in the genome of the fly, and is located in the beta-heterochromatic regi on at cytological division 80 on chromosome III, The expression patter n of this transcript shows that it is present in the tubular but not t he fibrillar muscles of the adult thorax, This expression pattern is c onsistent with this being a true SCP, In contrast, the expression patt ern of the transcript corresponding to the second cDNA clone is exclus ive to neural tissue, This transcript derives from a single copy gene, and is located at cytological position 89D on chromosome III, Compara tive analysis of the amino acid sequences from the proteins encoded by the two cDNAs with that of tbe original DCABP-23 protein indicates th at the purified DCABP-23 contained mainly the DCABP-A.1 protein, The i dentification of members of the SCP family of proteins in Drosophila, will allow for a future genetic investigation of the function of these ubiquitous proteins, (C) 1997 Elsevier Science Ltd, All rights reserv ed.