Human TEF-5 is preferentially expressed in placenta and binds to multiple functional elements of the human chorionic somatomammotropin-B gene enhancer.
We report the cloning of a cDNA encoding the human transcription factor hTEF-5, containing the TEA/ATTS DNA binding domain and related to the TEF family of transcription factors. hTEF-5 is expressed in skeletal and cardiac muscle, but the strongest expression is observed in the placenta and in placenta-derived JEG-3 choriocarcinoma cells. In correlation with its placental expression, we show that hTEF-5 binds to several functional enhansons of the human chorionic somatomammotropin (hCS)-B gene enhancer. We define a novel functional element in this enhancer comprising tandemly repeated sites to which hTEF-5 binds cooperatively. In the corresponding region of the hCS-A enhancer, which is known to be inactive, this element is inactivated by a naturally occurring single base mutation that disrupts hTEF-5 binding. We further show that the binding of the previously described placental protein f/chorionic somatomammotropin enhancer factor-1 to TEF-binding sites is disrupted by monoclonal antibodies directed against the TEA domain and that this factor is a proteolytic degradation product of the TEF factors. These results strongly suggest that hTEF-5 regulates the activity of the hCS-B gene enhancer.
Jacquemin
P
P
Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS/INSERM/ULP, Collège de France, B.P. 163-67404 Illkirch Cédex, France.
Martial
J A
JA
Davidson
I
I
D000595:Amino Acid Sequence; D001483:Base Sequence; D050976:Basic-Leucine Zipper Transcription Factors; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004742:Enhancer Elements, Genetic / Q000235:genetics; D005260:Female; D018507:Gene Expression Regulation, Developmental; D006801:Humans; D008969:Molecular Sequence Data; D010920:Placenta / Q000378:metabolism*; D010928:Placental Lactogen / Q000235:genetics* / Q000378:metabolism; D011247:Pregnancy; D000091262:TEA Domain Transcription Factors; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
D050976:Basic-Leucine Zipper Transcription Factors; D004268:DNA-Binding Proteins; D000091262:TEA Domain Transcription Factors; C106169:TEAD3 protein, human; C489490:TEF protein, human; D014157:Transcription Factors; D010928:Placental Lactogen