Zinc
Zinc is a chemical element; it has symbol Zn and atomic number 30. It is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic tabl ...
finger transcription factors or ZF-TFs, are
transcription factors
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The fun ...
composed of a
zinc finger
A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a ...
-
binding domain and any of a variety of transcription-factor effector-domains that exert their modulatory effect in the vicinity of any sequence to which the protein domain binds.
Zinc finger
A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a ...
protein transcription factors can be encoded by genes small enough to fit a number of such genes into a single
vector
Vector most often refers to:
* Euclidean vector, a quantity with a magnitude and a direction
* Disease vector, an agent that carries and transmits an infectious pathogen into another living organism
Vector may also refer to:
Mathematics a ...
, allowing the medical intervention and control of expression of multiple genes and the initiation of an elaborate cascade of events. In this respect, it is also possible to target a sequence that is common to multiple (usually functionally related) genes to control the transcription of all these genes with a single transcription factor. Also, it is possible to target a family of related genes by targeting and modulating the expression of the endogenous transcription factor(s) that control(s) them. They also have the advantage that the targeted sequence need not be symmetrical unlike most other DNA-binding motifs based on natural transcription factors that bind as dimers.
Applications
By targeting the ZF-TF toward a specific DNA sequence and attaching the necessary effector domain, it is possible to downregulate or upregulate the expression of the gene(s) in question while using the same DNA-binding domain.
The expression of a gene can also be downregulated by blocking
elongation by RNA polymerase (without the need for an effector domain) in the coding region or RNA itself can also be targeted.
Besides the obvious development of tools for the research of gene function, engineered ZF-TFs have therapeutic potential including correction of abnormal gene expression profiles (e.g.,
erbB-2 overexpression in human
adenocarcinomas
Adenocarcinoma (; plural adenocarcinomas or adenocarcinomata ; AC) is a type of cancerous tumor that can occur in several parts of the body. It is defined as neoplasia of epithelial tissue that has glandular origin, glandular characteristics, o ...
)
and anti-retrovirals (e.g. HIV-1
).
See also
*
Artificial transcription factor, of which the ZF-TF is a type
*
Gene therapy
Gene therapy is Health technology, medical technology that aims to produce a therapeutic effect through the manipulation of gene expression or through altering the biological properties of living cells.
The first attempt at modifying human DNA ...
*
Zinc finger
A zinc finger is a small protein structural motif that is characterized by the coordination of one or more zinc ions (Zn2+) which stabilizes the fold. The term ''zinc finger'' was originally coined to describe the finger-like appearance of a ...
proteins
*
Zinc finger chimera
*
Zinc finger nuclease
References
{{HIVpharm
Transcription factors
Zinc proteins