Ap-2 and Ikaros regulate transcription of human placental leucine aminopeptidase/oxytocinase gene.
P-LAP is identical with cystine aminopeptidase as oxytocinase. We previously located on the placental leucine aminopeptidase (P-LAP) gene the footprint site with the high promoter activity (FP3: -214 to -183) and found a possible interaction between it and AP-2 in choriocarcinoma cells. Here, we investigated FP3 in detail and identified the elements responsible for the high basal rate of transcription. Electrophoretic mobility shift assays demonstrated that FP3 would interact with Ikaros as well as AP-2. Further analysis using antibody against Ikaros confirmed that Ikaros was indeed present and bound to FP3. In addition, AP-2alpha and AP-2gamma antibodies supershifted the second complex at FP3. Functionally, mutations that eliminate AP-2 binding reduced promoter activity significantly, while those that eliminate Ikaros binding reduced promoter activity insignificantly. Double mutations of AP-2 and Ikaros decreased promoter activity progressively. We conclude that AP-2 is the main activator and Ikaros functions cooperatively with it for maximal expression of the human P-LAP gene.
Ito
Tomomi
T
Department of Obstetrics and Gynecology, Nagoya University School of Medicine, Nagoya, 466-8550, Japan.
Nomura
Seiji
S
Okada
Mayumi
M
Katsumata
Yoshinari
Y
Kikkawa
Fumitaka
F
Rogi
Tomohiro
T
Tsujimoto
Masafumi
M
Mizutani
Shigehiko
S
D001665:Binding Sites; D002460:Cell Line; D010122:Cystinyl Aminopeptidase / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000502:physiology*; D024202:Electrophoretic Mobility Shift Assay; D017930:Genes, Reporter; D006801:Humans; D051740:Ikaros Transcription Factor; D009154:Mutation; D011401:Promoter Regions, Genetic; D020218:Response Elements; D050656:Transcription Factor AP-2; D014157:Transcription Factors / Q000502:physiology*; D015533:Transcriptional Activation
D004268:DNA-Binding Proteins; C497239:IKZF1 protein, human; C493673:TFAP2A protein, human; C493679:TFAP2C protein, human; D050656:Transcription Factor AP-2; D014157:Transcription Factors; D051740:Ikaros Transcription Factor; D010122:Cystinyl Aminopeptidase; C105964:leucyl-cystinyl aminopeptidase