MAP6

Description

The MAP6 (microtubule associated protein 6) is a protein-coding gene located on chromosome 11.

Microtubule-associated protein 6 (MAP6) or stable tubule-only polypeptide (STOP or STOP protein) is a protein that in humans is encoded by the MAP6 gene. This gene encodes a microtubule-associated protein (MAP). The encoded protein is a calmodulin binding, and calmodulin-regulated protein that is involved in microtubule stabilization. MAP6 localization is present throughout neuronal maturation and axonal development. It protects microtubules under drug and cold induced depolymerization by reducing the shrinking rate and promoting rescue events. A deficit in MAP6 protein levels is characterized by behavioral impairments, most notably schizophrenia.

== Structure == A murine isoform of MAP6, MAP6-N, has 3 major domains: 12 calmodulin binding domains, 3 Mn domains, and 3-6 Mc domains.

Calmodulin-binding domains: 12 of the calmodulin-binding domains exist in MAP6-N. In vitro studies show that Ca+2-Calmodulin (CaM) binding to MAP6 prevents binding to microtubules. According to a model proposed by Ramkumar and collaborators, upon synaptic activity, the Ca+2-CaM complex forms, where it detaches MAP6 from adjacent microtubules, and activates Ca+2/calmodulin-dependent protein kinase II (CaMKII). When Ca+2 level decreases, CaM is released from MAP6 and is then phosphorylated by CaMKII. The phosphorylated MAP6 cannot re-associate with microtubules.

MAP6 plays a crucial role in maintaining microtubule stability in various cell types, particularly in neurons. It exhibits cold-stabilizing properties for microtubules, signifying its ability to preserve their structure under harsh conditions. MAP6 is involved in the development and maintenance of dendrites, the branching structures of neurons, by regulating the movement of lysosomes, cellular organelles responsible for waste removal, through its interaction with the TMEM106B protein. Furthermore, MAP6 regulates the transport of cargo along axons, the long extensions of neurons, by influencing the activity of the motor protein KIF5A. MAP6 also contributes to the growth of axons during the polarization of neurons, a process that establishes the distinct ends of a neuron.

MAP6 is also known as MAP6-N, MTAP6, N-STOP, STOP.

Associated Diseases

WES Whole Exome Sequencing

Clinical Exome Sequencing