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Zinc-finger
A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) in order to stabilize the fold. It was originally coined to describe the finger-like appearance of a hypothesized structure from the African clawed frog (''Xenopus laevis'') transcription factor IIIA. However, it has been found to encompass a wide variety of differing protein structures in eukaryotic cells. ''Xenopus laevis'' TFIIIA was originally demonstrated to contain zinc and require the metal for function in 1983, the first such reported zinc requirement for a gene regulatory protein followed soon thereafter by the Krüppel factor in ''Drosophila''. It often appears as a metal-binding domain in multi-domain proteins. Proteins that contain zinc fingers (zinc finger proteins) are classified into several different structural families. Unlike many other clearly defined supersecondary structures such as Greek keys or β hairpins, there are a number o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Finger Nucleases
Zinc-finger nucleases (ZFNs) are artificial restriction enzymes generated by fusing a zinc finger DNA-binding domain to a DNA-cleavage domain. Zinc finger domains can be engineered to target specific desired DNA sequences and this enables zinc-finger nucleases to target unique sequences within complex genomes. By taking advantage of endogenous DNA repair machinery, these reagents can be used to precisely alter the genomes of higher organisms. Alongside CRISPR/Cas9 and TALEN, ZFN is a prominent tool in the field of genome editing. Domains DNA-binding domain The DNA-binding domains of individual ZFNs typically contain between three and six individual zinc finger repeats and can each recognize between 9 and 18 basepairs. If the zinc finger domains perfectly recognize a 3 basepair DNA sequence, they can generate a 3-finger array that can recognize a 9 basepair target site. Other procedures can utilize either 1-finger or 2-finger modules to generate zinc-finger arrays with six ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
