TRPM4 Antibody – Rabbit Polyclonal

The protein encoded by this gene is a calcium-activated nonselective ion channel that mediates transport of monovalent cations across membranes, thereby depolarizing the membrane. The activity of the encoded protein increases with increasing intracellular calcium concentration, but this channel does not transport calcium. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2010]

TRPM4: Calcium-activated non selective (CAN) cation channel that mediates membrane depolarization. While it is activated by increase in intracellular Ca(2+), it is impermeable to it. Mediates transport of monovalent cations (Na(+) > K(+) > Cs(+) > Li(+)), leading to depolarize the membrane. It thereby plays a central role in cadiomyocytes, neurons from entorhinal cortex, dorsal root and vomeronasal neurons, endocrine pancreas cells, kidney epithelial cells, cochlea hair cells etc. Participates in T-cell activation by modulating Ca(2+) oscillations after T lymphocyte activation, which is required for NFAT-dependent IL2 production. Involved in myogenic constriction of cerebral arteries. Controls insulin secretion in pancreatic beta-cells. May also be involved in pacemaking or could cause irregular electrical activity under conditions of Ca(2+) overload. Affects T-helper 1 (Th1) and T-helper 2 (Th2) cell motility and cytokine production through differential regulation of calcium signaling and NFATC1 localization. Enhances cell proliferation through up-regulation of the beta-catenin signaling pathway. Defects in TRPM4 are the cause of progressive familial heart block type 1B (PFHB1B). It is a cardiac bundle branch disorder characterized by progressive alteration of cardiac conduction through the His-Purkinje system, with a pattern of a right bundle-branch block and/or left anterior hemiblock occurring individually or together. It leads to complete atrioventricular block causing syncope and sudden death. Belongs to the transient receptor (TC 1.A.4) family. LTrpC subfamily. TRPM4 sub-subfamily. 3 isoforms of the human protein are produced by alternative splicing.

Protein type: Membrane protein, integral; Membrane protein, multi-pass

Chromosomal Location of Human Ortholog: 19q13.33

Cellular Component: nucleoplasm; Golgi apparatus; endoplasmic reticulum; integral to membrane; plasma membrane

Molecular Function: calmodulin binding; calcium channel activity; calcium activated cation channel activity; ATP binding

Biological Process: vasoconstriction; regulation of membrane potential; protein sumoylation; regulation of T cell cytokine production; positive regulation of cell proliferation; dendritic cell chemotaxis; transmembrane transport

Disease: Progressive Familial Heart Block, Type Ib