D Sundar
Indian Institute of Technology (IIT) Delhi, New Delhi, India.
ABSTRACT
A technology for specifically targeting genes of humans has been the ‘Holy Grail’ in genetic medicine. The modular structure of zinc finger domain and modular recognition by zinc finger proteins make them the most versatile of DNA recognition motifs for designing artificial DNA binding proteins. Each zinc finger consists of about 30 amino acids and folds into ββα-structures, which is stabilized by the chelation of a zinc ion by the conserved Cys2His2 residues. Each finger typically recognizes a 3 bp DNA sequence by inserting the α-helix into the major groove of DNA. Binding of longer DNA sequences is achieved by linking several of these zinc finger motifs in tandem. Individual zinc finger (ZF) domains that recognize DNA triplets with high specificity and affinity can be used to create designer transcription factors and nucleases that are specific for nearly any site in the genome. The engineered ZFPs thus provide us with a powerful platform technology since other functionalities like non-specific FokI cleavage domain (N), transcription activator domains (A), transcription repressor domains (R) and methylases (M) can be fused to a ZFPs to form respectively zinc finger nucleases (ZFN), zinc finger transcription activators (ZFA), zinc finger transcription repressors (ZFR) and zinc finger methylases (ZFM). Computational informatics could play an important role in predicting ZFP specificity, identifying potential target sites and for designing the amino acid sequence of ZFP predicted to bind to a certain target site. Read More …