A novel 14-base-pair regulatory element is essential for in vivo expression of murine beta4-galactosyltransferase-I in late pachytene spermatocytes and round spermatids.
During murine spermatogenesis, beginning in late pachytene spermatocytes, the beta4-galactosyltransferase-I (beta4GalT-I) gene is transcribed from a male germ cell-specific start site. We had shown previously that a 796-bp genomic fragment that flanks the germ cell start site and contains two putative CRE (cyclic AMP-responsive element)-like motifs directs correct male germ cell expression of the beta-galactosidase reporter gene in late pachytene spermatocytes and round spermatids of transgenic mice (N. L. Shaper, A. Harduin-Lepers, and J. H. Shaper, J. Biol. Chem. 269:25165-25171, 1994). We now report that in vivo expression of beta4GalT-I in developing male germ cells requires an essential and previously undescribed 14-bp regulatory element (5'-GCCGGTTTCCTAGA-3') that is distinct from the two CRE-like sequences. This cis element is located 16 bp upstream of the germ cell-specific start site and binds a male germ cell protein that we have termed TASS-1 (transcriptional activator in late pachytene spermatocytes and round spermatids 1). The presence of the Ets signature binding motif 5'-GGAA-3' on the bottom strand of the TASS-1 sequence (underlined sequence) suggests that TASS-1 is a novel member of the Ets family of transcription factors. Additional transgenic analyses established that an 87-bp genomic fragment containing the TASS-1 regulatory element was sufficient for correct germ cell-specific expression of the beta-galactosidase reporter gene. Furthermore, when the TASS-1 motif was mutated by transversion, within the context of the original 796-bp fragment, transgene expression was reduced 12- to 35-fold in vivo.
Charron
M
M
The Cell Structure and Function Laboratory, The Oncology Center, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21287-8937, USA.
Shaper
N L
NL
Rajput
B
B
Shaper
J H
JH
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D051786:Cyclic AMP Response Element Modulator; D018983:DNA Footprinting; D004268:DNA-Binding Proteins / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D008957:Models, Genetic; D011401:Promoter Regions, Genetic; D020033:Protein Isoforms / Q000502:physiology; D012045:Regulatory Sequences, Nucleic Acid; D012097:Repressor Proteins; D013087:Spermatids / Q000201:enzymology; D013090:Spermatocytes / Q000201:enzymology*; D013091:Spermatogenesis / Q000235:genetics*; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000145:classification / Q000378:metabolism; D014158:Transcription, Genetic; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase / Q000096:biosynthesis* / Q000235:genetics
D004268:DNA-Binding Proteins; D020033:Protein Isoforms; D012097:Repressor Proteins; C120541:TASS-1 protein, mouse; D015534:Trans-Activators; D014157:Transcription Factors; D051786:Cyclic AMP Response Element Modulator; D006022:beta-N-Acetylglucosaminylglycopeptide beta-1,4-Galactosyltransferase