Cell cycle regulator of non-homologous end joining is a
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respon ...
that in humans is encoded by the CYREN
gene
In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
.
It prevents classical
non-homologous end joining
Non-homologous end joining (NHEJ) is a pathway that repairs double-strand breaks in DNA. NHEJ is referred to as "non-homologous" because the break ends are directly ligated without the need for a homologous template, in contrast to homology direct ...
, a method of repair of double-stranded DNA breaks.
This protein is therefore important in regulating
DNA repair
DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as radiation can cause DNA da ...
.
When alternatively spliced, is predicted to produce three different
micropeptides
Micropeptides (also referred to as microproteins) are polypeptides with a length of less than 100-150 amino acids that are encoded by short open reading frames (sORFs). In this respect, they differ from many other active small polypeptides, which ...
.
* MRI-1 was previously found to be a modulator of retrovirus infection.
* MRI-2 may be important in
non-homologous end joining
Non-homologous end joining (NHEJ) is a pathway that repairs double-strand breaks in DNA. NHEJ is referred to as "non-homologous" because the break ends are directly ligated without the need for a homologous template, in contrast to homology direct ...
(NHEJ) of DNA double strand breaks. In Co-Immunoprecipitation experiments, MRI-2 bound to
Ku70
Ku70 is a protein that, in humans, is encoded by the ''XRCC6'' gene.
Function
Together, Ku70 and Ku80 make up the Ku heterodimer, which binds to DNA double-strand break ends and is required for the non-homologous end joining (NHEJ) pathway ...
and
Ku80
Ku80 is a protein that, in humans, is encoded by the ''XRCC5'' gene. Together, Ku70 and Ku80 make up the Ku heterodimer, which binds to DNA double-strand break ends and is required for the non-homologous end joining (NHEJ) pathway of DNA repai ...
, two subunits of
Ku, which play a major role in the NHEJ pathway.
*MRI-3
References
DNA repair
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