Testis-specific expression of rat mitochondrial glycerol-3-phosphate dehydrogenase in haploid male germ cells.
Mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH) is regulated by multiple promoters in a tissue-specific manner. We characterized the testis-specific promoter C of the mGPDH gene and investigated the cellular localization of mGPDH within the testis. Electrophoretic mobility shift experiments identified a cAMP-response element (CRE) site at -57 that was active in the testis. An in vitro-translated CRE modulator (CREM) protein was able to bind this CRE site, and an anti-CREM antibody interfered with this complex. Ectopic expression of the testis-specific transcriptional activator CREMtau and protein kinase A in human hepatocarcinoma HepG2 cells activated a promoter C-driven luciferase construct in transient transfection experiments. Furthermore, mGPDH expression was undetectable in testis of CREM-deficient mice. The cellular localization of mGPDH expression and translation in adult rat testis was determined by in situ hybridization and immunohistochemistry techniques. The mGPDH transcripts were detected solely in postmeiotic germ cells. Expression of mGPDH was restricted from round spermatids to early elongating spermatids. The mGPDH protein was delayed in postmeiotic germ cells, restricted from late elongating spermatids to mature spermatids. Our results indicate that rat mGPDH is expressed by a testis-specific promoter from haploid male germ cells in a stage-specific manner.
Weitzel
Joachim M
JM
Institute of Medical Biochemistry and Molecular Biology, University Hospital Hamburg-Eppendorf, D-20246 Hamburg, Germany. weitzel@uke.uni-hamburg.de
Shiryaeva
Natalia B
NB
Middendorff
Ralf
R
Balvers
Marga
M
Radtke
Christiane
C
Ivell
Richard
R
Seitz
Hans J
HJ
D000818:Animals; D001483:Base Sequence / Q000235:genetics; D004586:Electrophoresis; D005993:Glycerolphosphate Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D008928:Mitochondria / Q000201:enzymology*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D013094:Spermatozoa / Q000378:metabolism*; D013737:Testis / Q000201:enzymology*; D014162:Transfection; D014407:Tumor Cells, Cultured
D005993:Glycerolphosphate Dehydrogenase