HemT-3, an alternative transcript of mouse gene HemT specific to male germcells

A number of genes are known to be expressed primarily in hematopoietic cell s and testis and are thought to function in the control of both blood cell and male germ cell differentiation. We have recently identified a mouse gen e, HemT, that encodes two alternatively spliced transcripts specific to hem atopoietic cells (HemT-1 and HemT-2) and kidney (HemT-2). We have now isola ted a third HemT transcript, HemT-3, that is found only in testis by Northe rn blot analysis and RT-PCR. Hem-3 is alternatively spliced and may be init iated differently from HemT-1 and HemT-2. RNA in-situ hybridization of test is from wild-type and germ-cell-deficient adult mice, as well as from mice at different developmental stages, indicates that HemT-3 is expressed only in early spermatocytes. HemT-3 cDNA has a major open reading frame related to a human glycosylphosphatidylinositol (GPI)-anchored protein, GML. Using an antibody generated against a peptide derived from the HemT-3 open readin g frame, we have detected a testis-specific 22 kDa protein by Western blot analysis. (C) 1999 Elsevier Science B.V. All rights reserved.