MatP

MATP is an acronym that can refer to more than one biology-related concept, most notably in human genetics and bacterial chromosome organization. In humans, MATP stands for Membrane-Associated Transporter Protein, an alternative name for the protein encoded by the SLC45A2 gene. SLC45A2/MATP is a multi-pass transmembrane transporter expressed in melanocytes and other pigment-related cells, and it localizes to melanosomes. It is implicated in the regulation of melanin synthesis, and genetic variants in SLC45A2 cause oculocutaneous albinism type 4 (OCA4), characterized by reduced pigment in the skin, hair, and eyes and related visual problems. The precise substrate and mechanism of MATP are not fully established, but the protein is thought to influence melanosome biology, potentially by affecting lumen pH or transporting solutes needed for melanin production. Normal MATP function supports pigmentation, while loss-of-function mutations contribute to hypopigmentation and ocular manifestations.

In bacteria, MatP refers to a chromosome-organizing protein that acts on the terminus region of the chromosome in many species, including Escherichia coli. MatP binds to matS sites within the Ter macrodomain and contributes to the spatial organization of the chromosome. It forms a complex with other structural proteins such as ZapB and MukB to anchor the terminus region and facilitate proper chromosome segregation during cell division. MatP activity is cell-cycle dependent and important for maintaining chromosomal architecture in many bacteria. The two uses of the acronym—MATP in humans and MatP in bacteria—are unrelated beyond sharing the same letters.