Oehler T, Arnold H, Biedenkapp H, Klempnauer K H
Zentrum für Molekulare Biologie, Universität Heidelberg, FRG.
Nucleic Acids Res. 1990 Apr 11;18(7):1703-10. doi: 10.1093/nar/18.7.1703.
The transforming protein encoded by the v-myb oncogene is a sequence-specific DNA-binding protein that is thought to be involved in the regulation of gene expression. The N-terminal region of the v-myb protein is composed of two highly conserved tandem repeat sequences of unknown function. It has been speculated that the N-terminal v-myb repeats might be crucial for DNA-binding, since N-terminal deletions destroy the DNA-binding activity of the v-myb protein. Here, we have studied the v-myb DNA-binding domain in more detail. Our results show that the N-terminal region of the v-myb protein is sufficient for specific DNA-binding. Dissection of this region suggests that both repeats are required for DNA-binding, but that both repeats play different roles in v-myb protein DNA interaction. We also show that the myb repeats of a drosophila melanogaster homolog of c-myb function as sequence-specific DNA-binding domain. Our results support the view that specific sequence-recognition, mediated by the conserved myb repeats, is a general feature of myb-related proteins.
由v-myb癌基因编码的转化蛋白是一种序列特异性DNA结合蛋白，被认为参与基因表达的调控。v-myb蛋白的N端区域由两个功能未知的高度保守串联重复序列组成。据推测，N端v-myb重复序列可能对DNA结合至关重要，因为N端缺失会破坏v-myb蛋白的DNA结合活性。在此，我们更详细地研究了v-myb DNA结合结构域。我们的结果表明，v-myb蛋白的N端区域足以实现特异性DNA结合。对该区域的剖析表明，两个重复序列对于DNA结合都是必需的，但两个重复序列在v-myb蛋白与DNA的相互作用中发挥不同作用。我们还表明，果蝇c-myb同源物的myb重复序列作为序列特异性DNA结合结构域发挥作用。我们的结果支持这样一种观点，即由保守的myb重复序列介导的特异性序列识别是myb相关蛋白的一个普遍特征。
