GATA-1 and GATA-4 transactivate inhibin/activin beta-B-subunit gene transcription in testicular cells.
We have recently demonstrated that a testicular GATA-binding protein, GATA-1, up-regulates the transcription of inhibin alpha-subunit gene through interaction with GATA motifs in the promoter region in MA-10, a mouse Leydig tumor cell line. In this study, we showed that both GATA-1 and GATA-4 also transactivated the transcription from the promoter for the 4.8-kb inhibin/activin beta-B-subunit gene transcripts, beta-B(4.8)-subunit promoter, in two testicular cell lines, MA-10 and MSC-1, which is a mouse Sertoli cell line. The abilities of GATA-1 and GATA-4 interacting with GATA and/or GATA-like sequences to transactivate the beta-B(4.8)-subunit promoter were next examined by mutation analysis. Mutations of GATA or GATA-like sequences caused no apparent effect or only a small decrease in the basal transcriptional activity of this promoter. However, mutation of the GATA motif at -65 markedly decreased 60-70% of the effect of GATA-1 on the transactivation of beta-B(4.8)-subunit promoter in both MA-10 and MSC-1 cells. In addition, mutation of the GATA motif in MSC-1 cells also reduced 40-50% of the effect of GATA-4 to transactivate this promoter. Interestingly, mutation of GATT at -42 caused a 70-90% increase in the transactivation of beta-B(4.8)-subunit promoter by GATA-1 or GATA-4. No significant change in the promoter activity was observed when GATT at -177 or GATC at -201 was mutated. Electrophoretic mobility shift assay confirmed the above observations that these GATA-binding proteins interacted with the GATA motif at -65 and GATT at -42, but not with GATC at -201 or GATT at -177. Serial deletion from the 5'-end of the basal promoter, from -226 to -90, markedly decreased the basal transcription, but increased the effect of GATA-1 on transactivation of the beta-B(4.8)-subunit promoter. In summary, our observations suggest that the two GATA-binding proteins transactivate the beta-B(4.8)-subunit promoter in testicular cells via complicated mechanisms. Both GATA-1 and GATA-4 factors act through the GATA motif at -65 and GATT at -42 to positively and negatively regulate the transcription from this promoter, respectively. Furthermore, GATA-1 may also interact directly or indirectly with DNA sequences at -180 to -90 to regulate the beta-B(4.8)-subunit promoter.
Feng
Z M
ZM
Population Council, New York, New York 10021, USA.
Wu
A Z
AZ
Zhang
Z
Z
Chen
C L
CL
D028341:Activins; D000818:Animals; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D050991:GATA4 Transcription Factor; D007265:Inhibins / Q000235:genetics* / Q000378:metabolism; D007985:Leydig Cells / Q000502:physiology; D008297:Male; D051379:Mice; D009154:Mutation; D010455:Peptides / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D051381:Rats; D017207:Rats, Sprague-Dawley; D017384:Sequence Deletion; D012708:Sertoli Cells / Q000502:physiology; D013737:Testis / Q000166:cytology* / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; D050991:GATA4 Transcription Factor; C494689:Gata1 protein, mouse; C494690:Gata1 protein, rat; D010455:Peptides; D014157:Transcription Factors; C044147:activin B; D028341:Activins; D007265:Inhibins