DNA-binding protein

DNA-binding proteins are a broad class of protein molecules that possess certain structural motifs (i.e. helices) which enable them to stably bind both double- or single-stranded DNA. Examples of such proteins would be those whose primary function is to regulate the expression of specific genes (termed transcription factors), those proteins involved in the packaging of DNA within the nucleus (histones), nucleic acid dependent-polymerases involved in DNA replication and the transcription of mRNA, or any of many accessory proteins which are involved in these processes.