Membrane-associated transporter protein (MATP), also known as solute carrier family 45 member 2 (SLC45A2) or melanoma antigen AIM1, is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

that in humans is encoded by the ''SLC45A2''

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

Function

SLC45A2 is a

transporter protein A transport protein (variously referred to as a transmembrane pump, transporter, escort protein, acid transport protein, cation transport protein, or anion transport protein) is a protein that serves the function of moving other materials within ...

that mediates

melanin Melanin (; ) is a family of biomolecules organized as oligomers or polymers, which among other functions provide the pigments of many organisms. Melanin pigments are produced in a specialized group of cells known as melanocytes. There are ...

synthesis. It may regulate the pH of the

melanosome A melanosome is an organelle found in animal cells and is the site for synthesis, storage and transport of melanin, the most common light-absorbing pigment found in the animal kingdom. Melanosomes are responsible for color and photoprotectio ...

, affecting

tyrosinase Tyrosinase is an oxidase that is the rate-limiting enzyme for controlling the production of melanin. The enzyme is mainly involved in two distinct reactions of melanin synthesis otherwise known as the Raper–Mason pathway. Firstly, the hydroxy ...

activity. SLC45A2 is also a

melanocyte Melanocytes are melanin-producing neural-crest, neural crest-derived cell (biology), cells located in the bottom layer (the stratum basale) of the skin's epidermis (skin), epidermis, the middle layer of the eye (the uvea), the inner ear, vagina ...

differentiation antigen that is expressed in a high percentage of

melanoma Melanoma is the most dangerous type of skin cancer; it develops from the melanin-producing cells known as melanocytes. It typically occurs in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In very rare case ...

cell lines. A similar sequence gene in

medaka The Japanese rice fish (''Oryzias latipes''), also known as the medaka, is a member of genus ''Oryzias'' ( ricefish), the only genus in the subfamily Oryziinae. This small (up to about ) native of Japan is a denizen of rice paddies, marshes, po ...

fish, 'B,' encodes a transporter that mediates melanin synthesis. Mutations in this gene are a cause of

oculocutaneous albinism Oculocutaneous albinism is a form of Albinism in humans, albinism involving the human eye, eyes (''wikt:oculo-#Prefix, oculo-''), the human skin, skin (''-wikt:cutaneous#Adjective, cutaneous''), and the hair. Overall, an estimated 1 in 20,000 peo ...

type 4. Alternative splicing results in multiple transcript variants encoding different isoforms. Protein expression is localized to the melanosome, and analysis of the by knockdown of RNA expression leads to altered melanosome pH potentially altering tyrosinase function by affecting copper binding. In

melanocytic cell Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and heart found ...

types, the SLC45A2 gene is regulated by

microphthalmia-associated transcription factor Microphthalmia-associated transcription factor also known as class E basic helix-loop-helix protein 32 or bHLHe32 is a protein that in humans is encoded by the ''MITF'' gene. MITF is a basic helix-loop-helix leucine zipper transcription factor ...

. SLC45A2 has been found to play a role in pigmentation in several species. In humans, it has been identified as a factor in the light skin of Europeans and as an ancestry-informative marker for distinguishing Sri Lankan from European ancestry. Mutations in the gene have also been identified as the cause of human Type IV

. SLC45A2 is the so-called

cream gene The cream gene is responsible for a number of Equine coat color, horse coat colors. Horses that have the cream gene in addition to a base coat color that is chestnut (coat), chestnut will become palomino if they are heterozygous, having one co ...

responsible in horses for buckskin, palomino and cremello coloration, while a mutation in this gene underlies the

white tiger The white tiger (ashy tiger) is a leucistic morph of the tiger, typically the Bengal tiger. It is occasionally reported in the Indian wilderness. It has the typical black stripes of a tiger, but its coat is otherwise white or near-white, and ...

variant. In dogs a mutation to this gene causes white fur, pink skin, and blue eyes. SLC45A2 was identified as a

tumor-associated antigen with high tumor specificity and reduced potential for autoimmune toxicity, and is currently in clinical development as a target for T-cell based immunotherapy.

References

External links

GeneReviews/NCBI/NIH/UW entry on Oculocutaneous Albinism Type 4
Solute carrier family {{membrane-protein-stub

Function

See also

References

Further reading

External links