Ankyrin-B (ANK2) Antibody – Mouse Monoclonal

This gene encodes a member of the ankyrin family of proteins that link the integral membrane proteins to the underlying spectrin-actin cytoskeleton. Ankyrins play key roles in activities such as cell motility, activation, proliferation, contact and the maintenance of specialized membrane domains. Most ankyrins are typically composed of three structural domains: an amino-terminal domain containing multiple ankyrin repeats; a central region with a highly conserved spectrin binding domain; and a carboxy-terminal regulatory domain which is the least conserved and subject to variation. The protein encoded by this gene is required for targeting and stability of Na/Ca exchanger 1 in cardiomyocytes. Mutations in this gene cause long QT syndrome 4 and cardiac arrhythmia syndrome. Multiple transcript variants encoding different isoforms have been described. [provided by RefSeq, Dec 2011]

ANK2: In skeletal muscle, required for proper localization of DMD and DCTN4 and for the formation and/or stability of a special subset of microtubules associated with costameres and neuromuscular junctions. Attaches integral membrane proteins to cytoskeletal elements. Also binds to cytoskeletal proteins. Required for coordinate assembly of Na/Ca exchanger, Na/K ATPase and InsP3 receptor at sarcoplasmic reticulum sites in cardiomyocytes. Required for the coordinated expression of the Na/K ATPase, Na/Ca exchanger and beta-2-spectrin (SPTBN1) in the inner segment of rod photoreceptors. Required for expression and targeting of SPTBN1 in neonatal cardiomyocytes and for the regulation of neonatal cardiomyocyte contraction rate. Defects in ANK2 are the cause of long QT syndrome type 4 (LQT4); also known as sick sinus syndrome with bradycardia. Long QT syndromes are heart disorders characterized by a prolonged QT interval on the ECG and polymorphic ventricular arrhythmias. They cause syncope and sudden death in response to exercise or emotional stress. LQT4 displays many atypical features compared to classical long QT syndromes, including pronounced sinus bradycardia, polyphasic T waves and atrial fibrillation. Cardiac repolarization defects may be not as severe as in classical LQT syndromes and prolonged QT interval on EKG is not a consistent feature. 4 isoforms of the human protein are produced by alternative splicing.

Protein type: Motility/polarity/chemotaxis; Adaptor/scaffold

Chromosomal Location of Human Ortholog: 4q25-q27

Cellular Component: neuron projection; costamere; integral to plasma membrane; basolateral plasma membrane; T-tubule; M band; Z disc; cytosol; lipid raft; postsynaptic membrane; cytoskeleton; perinuclear region of cytoplasm; apical plasma membrane; plasma membrane; intracellular; A band; sarcolemma

Molecular Function: protein binding, bridging; protein binding; potassium channel regulator activity; enzyme binding; spectrin binding; structural constituent of cytoskeleton; protein kinase binding; ATPase binding

Biological Process: cellular calcium ion homeostasis; axon guidance; protein stabilization; regulation of heart rate; protein localization in organelle; T-tubule organization and biogenesis; response to methylmercury; positive regulation of potassium ion transport; regulation of protein stability; regulation of calcium ion transport; positive regulation of calcium ion transport; regulation of release of sequestered calcium ion into cytosol; paranodal junction assembly; cardiac muscle contraction

Disease: Cardiac Arrhythmia, Ankyrin-b-related