Answer to Question #148896 in Biochemistry for Sara Kanwal

Question

There are three proteins which are functionally distinct, but at the same time two of them are able to bind DNA while third one is not. Name that specialized region/structure which is common to these two proteins. While there is one structural state/level of the proteins where all three of them cannot bind to DNA (are not functional) which one is that.

Answer 1

DNA-binding proteins include transcription factors which modulate the process of transcription, various polymerases, nucleases which cleave DNA molecules, and histones which are involved in chromosomes packaging and transcription in the cell nucleus. DNA-binding proteins can incorporate such domains as the zinc finger, the helix turn helix, and the leucine zipper -among many others- that facilitate binding to nucleic acid. There are also more unusual examples such as transcription like activator factors