Genomic organization of a mouse glyceraldehyde 3-phosphate dehydrogenase gene (Gapd-s) expressed in post-meiotic spermatogenic cells.
The Gapd-s gene encodes an isoform of the glyceraldehyde 3-phosphate dehydrogenase enzyme expressed only in post-meiotic spermatogenic cells. Two clones containing the Gapd-s gene were isolated from a mouse genomic library. Sequencing and restriction enzyme analysis demonstrated that this single-copy gene contains 11 exons and spans 9596 base pairs. The locations of Gapd-s exons and introns are conserved when compared to the corresponding portions of the chicken and human somatic Gapd genes. The promoter region contains no TATA box, although there is a potential SP1 recognition site within exon 1. Like other TATA-less genes, primer extension analysis reveals some heterogeneity in the site of transcription initiation with Gapd-s transcripts initiating from three discrete sites. Northern analysis demonstrated that a 1.5-kb Gapd-s mRNA is expressed in the testis in at least three mammalian orders, indicating that the Gapd-s gene appeared early in mammalian evolution. Using GAPD-deficient bacteria, mouse GAPD-S was shown to be capable of functioning as a glycolytic enzyme. Since GAPD has been proposed to be a key enzyme regulating glycolysis in spermatogenic cells, GAPD-S may represent a potential target for toxicological or contraceptive agents affecting fertility by interfering with glycolysis.
Welch
J E
JE
Gamete Biology Section, National Institutes of Health, Research Triangle Park, NC 27709, USA.
Brown
P R
PR
O'Brien
D A
DA
Eddy
E M
EM
D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D004247:DNA; D005091:Exons; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics* / Q000378:metabolism; D006019:Glycolysis; D007438:Introns; D008297:Male; D008540:Meiosis; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D051381:Rats; D017207:Rats, Sprague-Dawley; D013045:Species Specificity; D013094:Spermatozoa / Q000166:cytology / Q000201:enzymology*; D016385:TATA Box; D014158:Transcription, Genetic
D004247:DNA; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases