Differential potency and trans‐activation of normal and mutant T24 human H‐ras1 gene promoters

FEBS Letters

Pintzas, Alex¹  Spandidos, Demetrios A.² 

[1] Hellenic Pasteur Institute, 127 Vas Sofias Ave, Athens 11521, Greece;The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Bearsden, Glasgow G61 1BD, Scotland

关键词: Trans-activation;    H-ras oncogene;    Polyoma oncogene;   

DOI  :  10.1016/0014-5793(88)80751-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

We have employed a short-term transfection assay system in which we monitored the transient expression of the chloramphenicol acetyltransferase (CAT) gene linked to the promoter region of the normal and mutant T24 H-ras1 gene or the human ε-globin gene in Chinese hamster lung (CHL) cells or cells derived from them which carry and express one or the other of the polyoma virus early genes. Our findings can be summarized as follows: (i) The mutant T24 H-ras1 promoter region behaves as a stronger promoter than the H-ras1 gene in all these types of cells as well as in rat 208F fibroblast cells. (ii) In CHL cells expressing the polyoma large T antigen the normal and mutant T24 Ha-ras1 promoters are not trans-activated in these cells and only a 2.5-fold activation of the ε-globin promoter is observed. (iii) In cells expressing the polyoma middle T antigen both the normal and mutant H-ras1 are trans-activated whereas transcription from the ε-globin promoter is not affected when compared to the normal CHL cells. (iv) In cells expressing the polyoma small T antigen the normal and mutant H-ras1 as well as the ε-globin promoters are trans-activated. We suggest from these data that a tissue-specific element exists in the promoter region of the H-ras1 gene and that the polyoma middle and small T antigens trigger the expression of proteins that trans-activate these promoters.

【 授权许可】

Unknown