3. Introduction
• Zinc finger proteins are among the most abundant proteins in
eukaryotic genomes
• These are present in tandem repeats
• Zinc ion holding the DNA folds
• Each zinc motif consists of 30 amino acids and fold into beta
beta alpha structure.
4. History
Zinc fingers were first identified in the Xenopus laevis, in
the laboratory of Aaron Klug(British Chemist and
Biophysicist).
Revealed that the binding strength of the transcription
IIIA is because of the presence of the Zinc coordinating
finger like structures. (Miller et al., 1985)
(Also known as African Clawed Toad. )
(The word Xenopus means "strange foot" and laevis
means "smooth)
5. Zinc protein family
• Largest known DNA binding family in the multicellular organisms.
• Composed of two Beta layers and one Alpha helix.
• Two cysteine and two histidine residues located in certain positions
bind zinc to stabilize the structure.
• Four other amino acid residues localized in specific positions in the
N-terminal region of the α-helix participate in DNA binding by
interacting with hydrogen donors and acceptors exposed in the DNA
major groove
• Plays role in - Development, differentiation, and suppression of
malignant cell transformation
6. Zinc finger motif
• It is a part of protein that can bind to DNA
• Zinc finger domains typically consist of two
antiparallel beta sheets, each carrying a
cysteine residue, and an alpha helix carrying
two histidine residue.(C2H2)
• The cysteine and histidine residue bind a zinc
atom.
• Many transcription factors such as TFIIIA,
regulatory proteins.
• and other proteins that interact with DNA, all
contain zinc finger
7.
8. Function
• Their functions are extraordinarily diverse and
• include DNA recognition,
• RNA packaging,
• transcriptional activation,
• regulation of apoptosis,
• protein folding and assembly, and
• lipid binding.
9. Application
• Zinc-finger proteins (ZFPs) that recognize novel DNA
sequences are the basis of a powerful technology platform with
many uses in drug discovery and therapeutics
• ZFP-mediated regulation of endogenous genes could make it
possible to use genes in a drug discovery application that would
otherwise require securing intellectual property rights for a
corresponding complementary DNA sequence.
• ZFP transcription factors (ZFP TFs) are made by combining the
ZFPs with domains that either activate or repress genes. ZFP
TFs are used in drug discovery to regulate genes for target
validation, high-throughput screening and human therapeutics.
10. Application
• The most common applications for engineered zinc finger
arrays include zinc finger transcription factors and zinc finger
nucleases.
11. Reference
• Klug A (2010). "The discovery of zinc fingers and their
applications in gene regulation and genome
manipulation". Annual Review of Biochemistry. 79: 213–31
• Klug A, Rhodes D (1987). "Zinc fingers: a novel protein fold for
nucleic acid recognition". Cold Spring Harbor Symposia on
Quantitative Biology. 52: 473–82