Exonuclease 1 is an enzyme

Enzyme

Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...

 that in humans is encoded by the EXO1 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.

This gene encodes a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 with 5' to 3' exonuclease activity as well as an RNase H

RNase H

The enzyme RNase H is a non-specific endonuclease and catalyzes the cleavage of RNA via a hydrolytic mechanism. Members of the RNase H family can be found in nearly all organisms, from archaea to bacteria and eukaryota....

 activity (endonuclease activity cleaving RNA on DNA/RNA hybrid). It is similar to the Saccharomyces cerevisiae protein Exo1 which interacts with Msh2 and which is involved in DNA mismatch repair

DNA mismatch repair

DNA mismatch repair is a system for recognizing and repairing erroneous insertion, deletion and mis-incorporation of bases that can arise during DNA replication and recombination, as well as repairing some forms of DNA damage....

 and homologous recombination

Homologous recombination

Homologous recombination is a type of genetic recombination in which nucleotide sequences are exchanged between two similar or identical molecules of DNA. It is most widely used by cells to accurately repair harmful breaks that occur on both strands of DNA, known as double-strand breaks...

. Alternative splicing of this gene results in three transcript variants encoding two different isoforms.

Interactions

Exonuclease 1 has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with MSH2

MSH2

MSH2 is a gene commonly associated with Hereditary nonpolyposis colorectal cancer.-Interactions:MSH2 has been shown to interact with Exonuclease 1, MSH3, MSH6, CHEK2, MAX, Ataxia telangiectasia and Rad3 related and BRCA1.-Further reading:...

 and MLH1

MLH1

MutL homolog 1, colon cancer, nonpolyposis type 2 , also known as MLH1, is a human gene located on Chromosome 3. It is a gene commonly associated with hereditary nonpolyposis colorectal cancer.It can also be associated with Turcot syndrome....

.

Further reading