Transcription factor 7-like 2 (T-cell specific, HMG-box) also known as TCF7L2 or TCF4 is 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...

 acting as a transcription factor

Transcription factor

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow of genetic information from DNA to mRNA...

. In humans this protein is encoded by the TCF7L2 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...

. A variant of the protein is linked to higher risk to develop type 2 diabetes.

Function

TCF7L2 is a transcription factor

Transcription factor

In molecular biology and genetics, a transcription factor is a protein that binds to specific DNA sequences, thereby controlling the flow of genetic information from DNA to mRNA...

 influencing the transcription

Transcription (genetics)

Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...

 of several genes

Gênes

Gênes is the name of a département of the First French Empire in present Italy, named after the city of Genoa. It was formed in 1805, when Napoleon Bonaparte occupied the Republic of Genoa. Its capital was Genoa, and it was divided in the arrondissements of Genoa, Bobbio, Novi Ligure, Tortona and...

 thereby exerting a large variety of functions within the cell. It is a member of the Wnt signaling pathway

Wnt signaling pathway

The Wnt signaling pathway is a network of proteins best known for their roles in embryogenesis and cancer, but also involved in normal physiological processes in adult animals.-Discovery:...

. Stimulation of the pathway leads to the association of β-catenin

Beta-catenin

Beta-catenin is a protein that in humans is encoded by the CTNNB1 gene. In Drosophila, the homologous protein is called armadillo...

 with BCL9

BCL9

B-cell CLL/lymphoma 9 protein is a protein that in humans is encoded by the BCL9 gene.Common variations in the BCL9 gene, which is in the distal area, confer risk of schizophrenia and may also be associated with bipolar disorder and major depressive disorder. -Further reading:...

, translocation to the nucleus, and association with TCF7L2, which in turn results in the activation of Wnt

Wnt signaling pathway

The Wnt signaling pathway is a network of proteins best known for their roles in embryogenesis and cancer, but also involved in normal physiological processes in adult animals.-Discovery:...

 target genes, specifically repressing proglucagon synthesis in enteroendocrine cells.

Disease implications

TCF7L2 is implicated in a large variety of diseases. Several single nucleotide polymorphism

Single nucleotide polymorphism

A single-nucleotide polymorphism is a DNA sequence variation occurring when a single nucleotide — A, T, C or G — in the genome differs between members of a biological species or paired chromosomes in an individual...

s are associated with type 2 diabetes. In European populations it was found to be a major determinant of type 2 risk.

A frameshift mutation

Frameshift mutation

A frameshift mutation is a genetic mutation caused by indels of a number of nucleotides that is not evenly divisible by three from a DNA sequence...

 of TCF7L2 is implicated in colorectal cancer

Colorectal cancer

Colorectal cancer, commonly known as bowel cancer, is a cancer caused by uncontrolled cell growth , in the colon, rectum, or vermiform appendix. Colorectal cancer is clinically distinct from anal cancer, which affects the anus....

. Variants of the gene are most likely involved in many other cancer types.

Name confusion

While TCF4 is sometimes used as an alias symbol for TCF7L2, it is also the symbol officially approved by the HUGO Gene Nomenclature Committee

HUGO Gene Nomenclature Committee

The HUGO Gene Nomenclature Committee approves a unique and meaningful name for every known human gene based on a query of experts. In addition to a long name, the HGNC also assigns an abbreviation to every gene...

 for the transcription factor 4

TCF4

Transcription factor 4, also known as immunoglobulin transcription factor 2 and TCF4, is a protein acting as a transcription factor. In humans this protein is encoded by the TCF4 gene.- Function :...

gene.

Further reading

External links

• TCF7L2 here called TCF4 features on this Wnt pathway web site: Wnt signalling molecules TCFs
• Structure determination of TCF7L2: PDB entry 2GL7 and related publication on PubMed
• PubMed GeneRIFs (summaries of related scientific publications) - http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?itool=gene_full_report&db=gene&cmd=Display&dopt=gene_pubmed_rif&from_uid=6934
• Weizmann Institute GeneCard for TCF7L2