Androcam, a potential testis-specific calcium sensor. P. Cornwell , K. Beckingham. Department of Biochemistry & Cell Biology, Rice University, Houston, TX.

   We have previously described Androcam (Acam) as a testis-specific protein 67% identical to the universal calcium signaling protein, calmodulin. Our current work is focused on identifying mutations to the gene and finding binding partners of the protein. We have uncovered four putative Acam mutant lines that exhibit marked male sterility by screening the Wakimoto/Lindsley collection of male sterile mutants, which is a subset of the Zuker viable mutant collection. Previously, we found that in primary spermatocytes Acam initially localizes to the giant Y chromosome loop (kl-3). The only other protein known to localize to loop kl-3 is a leucyl aminopeptidase, therefore we are investigating whether Acam and leucyl aminopeptidase directly interact by immunoprecipitation, immunolocalization, and proteomics techniques. Unexpectedly, we also discovered that Acam is part of a tightly linked cluster of three genes, all of which are closely related to calmodulin. Based on the sequence of this gene cluster and the transcripts generated from it, Acam may be transcribed as a polycistronic message with at least one other of these genes.