Folate receptor gamma 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, respo ...

that in humans is encoded by the FOLR3

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 ba ...

. It is involved in up-take of

folic acid Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...

Gene location

The ''FOLR'' multi-gene family (''FOLR1'', ''FOLR2'' and ''FOLR3'') is localized to chromosome 11q13.3–q14.1, and encodes the gene products FRα, β and γ, respectively.

Tissue distribution

FOLR3 is localized in

haematopoietic Haematopoiesis (, from Greek , 'blood' and 'to make'; also hematopoiesis in American English; sometimes also h(a)emopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cells. ...

tissue, such as spleen and bone marrow, and is present as a

secretory protein A secretory protein is any protein, whether it be endocrine or exocrine, which is secreted by a cell. Secretory proteins include many hormones, enzymes, toxins, and antimicrobial peptides. Secretory proteins are synthesized in the endoplasmic ret ...

. FOLR3 expresses in humans rather than mice and rats.

Function

The ''FOLR3'' gene is polymorphic due to a nonsense mutation resulting in a truncated protein; FRγ, which can bind folic acid. ''FOLR3'' genes each consist of 5 exons, 4 introns and 1 promoter that encodes a single transcript.

Clinical significance

Expression of FOLR3 is correlated more strongly with plasma

homocysteine Homocysteine is a non-proteinogenic α-amino acid. It is a homologue of the amino acid cysteine, differing by an additional methylene bridge (-CH2-). It is biosynthesized from methionine by the removal of its terminal Cε methyl group. In the b ...

(Hcy) than

FOLR1 Folate receptor 1 (Folate receptor alpha, FOLR1) is a protein that in humans is encoded by the ''FOLR1'' gene. The protein encoded by this gene is a member of the folate receptor (FOLR) family. Members of this family have a high affinity for foli ...

and

FOLR2 Folate receptor beta is a protein that in humans is encoded by the ''FOLR2'' gene. The protein encoded by this gene is a member of the folate receptor (FOLR) family. Members of this gene family have a high affinity for folic acid and for several ...

. FOLR3 may decrease plasma Hcy compared with other FOLRs. It was demonstrated that FOLR3 can metabolize both intracellular Hcy and extracellular Hcy. These results indicate that an increase in FOLR3 may effectively ameliorate Hcy in the blood and weaken Hcy-induced toxicity, even in tissues with the low level of FOLR1 and FOLR2 expression.

References

{{protein-stub Membrane proteins