| 摘要 |
<p>The present invention relates to chimeric transcriptional activators. The chimeric transcription activator protein contains at least one composite transcription activation domain ("TAD") and at least one DBD. The composite TAD comprises a continuous polypeptide region containing two or more component polypeptide regions (also referred to as "activation tags"), at least two of which do not occur together in the same gene product in nature. In certain of these embodiments the chimeric protein comprises a ligand binding domain for allosteric activation, e.g. a receptor domain capable of binding a cell permeant ligand such as tetracycline or an analog thereof or a steroid such as RU486 or ecdysone, for example. In such cases, the chimeric transcription activator selectively activates transcription of a target gene in the presence of the respective ligand. In other embodiments the chimeric transcription activator is capable of activating target gene expression constitutively, i.e., without the need for the presence of any such ligand.</p> |
