Codon reassignment is the
biological process via which the
genetic code
The genetic code is the set of rules used by living cells to translate information encoded within genetic material ( DNA or RNA sequences of nucleotide triplets, or codons) into proteins. Translation is accomplished by the ribosome, which links ...
of a cell is changed as a response to the environment. It may be caused by alternative
tRNA
Transfer RNA (abbreviated tRNA and formerly referred to as sRNA, for soluble RNA) is an adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length (in eukaryotes), that serves as the physical link between the mRNA and the amino ...
aminoacylation
Aminoacylation is the process of adding an aminoacyl group to a compound.
See also
* Acylation
* tRNA aminoacylation
* Transfer RNA-like structures
References
Organic reactions
{{Reaction-stub ...
, in which the cell modifies the target
aminoacid of some particular type of transfer-RNA.
This process has been identified in
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...
,
yeast
Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constit ...
and human
cancer cell
Cancer cells are cells that divide continually, forming solid tumors or flooding the blood with abnormal cells. Cell division is a normal process used by the body for growth and repair. A parent cell divides to form two daughter cells, and these d ...
s.
In human cancer cells, codon reassignment can be triggered by
tryptophan
Tryptophan (symbol Trp or W)
is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic ...
depletion, resulting in proteins where the tryptophan aminoacid is substituted by
phenylalanine.
See also
*
Expanded genetic code
An expanded genetic code is an artificially modified genetic code in which one or more specific codons have been re-allocated to encode an amino acid that is not among the 22 common naturally-encoded proteinogenic amino acids.
The key prerequisit ...
References
{{Biology-stub
Genetics
Amino acids
Biological processes
Bacteria
Yeasts
Cancer