Expression cloning is a technique in
DNA cloning that uses
expression vectors to generate a library of clones, with each clone expressing one
protein. This ''expression library'' is then screened for the property of interest and clones of interest are recovered for further analysis. An example would be using an expression library to isolate genes that could confer
antibiotic resistance
Antimicrobial resistance (AMR) occurs when microbes evolve mechanisms that protect them from the effects of antimicrobials. All classes of microbes can evolve resistance. Fungi evolve antifungal resistance. Viruses evolve antiviral resistance. ...
.
Expression vectors
Expression vectors are a specialized type of
cloning vector
A cloning vector is a small piece of DNA that can be stably maintained in an organism, and into which a foreign DNA fragment can be inserted for cloning purposes. The cloning vector may be DNA taken from a virus, the cell of a higher organism, or ...
in which the transcriptional and translational signals needed for the regulation of the gene of interest are included in the cloning vector. The transcriptional and translational signals may be synthetically created to make the expression of the gene of interest easier to regulate.
Purpose
Usually the ultimate aim of expression cloning is to produce large quantities of specific
proteins. To this end, a
bacterial expression
clone
Clone or Clones or Cloning or Cloned or The Clone may refer to:
Places
* Clones, County Fermanagh
* Clones, County Monaghan, a town in Ireland
Biology
* Clone (B-cell), a lymphocyte clone, the massive presence of which may indicate a pathologi ...
may include a
ribosome
Ribosomes ( ) are macromolecular machines, found within all cells, that perform biological protein synthesis (mRNA translation). Ribosomes link amino acids together in the order specified by the codons of messenger RNA (mRNA) molecules to ...
binding site (
Shine-Dalgarno sequence) to enhance translation of the gene of interest's mRNA, a
transcription termination sequence, or, in
eukaryotes
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacte ...
, specific sequences to promote the
post-translational modification of the protein product.
See also
Molecular cell biology*
genetics
*
gene expression
Gene expression is the process by which information from a gene is used in the synthesis of a functional gene product that enables it to produce end products, protein or non-coding RNA, and ultimately affect a phenotype, as the final effect. The ...
*
Transcription (genetics)
*
translation
*
λ phage
*
pBR322
References
Genetics techniques
Molecular genetics
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