Zinc Finger Nuclease (ZFN)

From MicrobeWiki, the student-edited microbiology resource

Introduction

Electron micrograph of the Ebola Zaire virus. This was the first photo ever taken of the virus, on 10/13/1976. By Dr. F.A. Murphy, now at U.C. Davis, then at the CDC.


Zinc finger nucleases (ZFNs) are enzymes composed of a DNA binding-domain and a DNA cleaving-domain. The DNA cleaving-domain can be used to create a double-stranded break in DNA at select points, genetic material can then added between the gap to create knockout genes or other modifications makes useful tools for genetic engineering. By

History

While other gene targeting procedures have existed for quite some time, the success of earlier methods were dependent on several factors including homologous recombination. Also, while genetic changes were observed in fungi like Saccharomyces cerevisiae and bacteria, most methods did not work on eukaryotic organisms. However, when studies in the 80s revealed that double-stranded DNA breaks greatly increased the frequency of recombination and thus successful genetic modifiactions, tools such as ZFNs became favored. Previously, stem cells were required (Rudin et. al.).

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Legend/credit: Diagram of a zinc finger nuclease. The zinc fingers are part of the binding-domain and have precisely identified and bound to a group of matching nucleobases in the DNA sequence. The cleaving-domains are Fok 1, which make a break in the DNA in both strands. Image credit to Stewart, C. N. and Burris, J. Jr.
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Superscript: Fe3+

thumb||300px||right|Diagram of a zinc finger nuclease. The zinc fingers are part of the binding-domain and have precisely identified and bound to a group of matching nucleobases in the DNA sequence. The cleaving-domains are Fok 1, which make a break in the DNA in both strands. Image credit to [http://www.arpa-e.energy.gov/sites/default/files/documents/files/Stewart_Bio_Tool_Pres_10_6_11.pdf Stewart, C. N. and Burris, J. Jr.]




Section 1


Include some current research in each topic, with at least one figure showing data.

Section 2


Include some current research in each topic, with at least one figure showing data.

Section 3


Include some current research in each topic, with at least one figure showing data.

Conclusion


Overall paper length should be 3,000 words, with at least 3 figures.

References

Dana Carroll. "Genome engineering with zinc-finger nucleases". Genetics. 2011. Volume 188(4). p. 773–782.

Porteus, M. H. and Carroll, D. "Gene targeting using zinc finger nucleases". Nature Biotechnology. 2005. Volume 23. p. 967-973.

Rudin,N., Sugarman, E., and Haber, J. E. "Genetic and Physical Analysis of Double-Strand Break Repair and Recombination in Saccharomyces Cerevisiae" Genetics. 1989. Volume 122(3). p. 519–534.

Kim, Y. K., Cha, J., and Chandrasegran, S. "restriction enzymes: Zinc finger fusions to Fok I cleavage domain" pnas. 1996. Volume 93. p. 1156-1160.

Santiago, Y., Chan, E., Liu, P., Orlando, S., Zhang, L., Urnov, F., Holmes, M., Guschin, D., Waite, A. Miller, J. C., Rebar, E. J., Gregory, P. D., Klug, A., and Collingwood, T. N. "Targeted gene knockout in mammalian cells by using engineered zinc-finger nucleases" pnas. 2008. Volume 105. p. 5809-5814.