Explain the Transcription Factor of Zinc?

Zinc is an important structural component of DNA- binding proteins also known as 'transcription factors'. These transcription factors contain 'zinc fingers'. The term zinc finger is used mainly to denote the configuration of the protein, which looks like fingers. It contains a series of polypeptide loops resulting from twisting and coiling of the cysteine and histidine residues. Zinc is ligated to these two amino acids. The series of loops give rise to zinc fingers. These zinc containing transcription factors bind to promoter sequences of specific genes and regulates transcription.