ACTN2

Alpha actinins belong to the spectrin gene superfamily which represents a diverse group of cytoskeletal proteins, including the alpha and beta spectrins and dystrophins. Alpha actinin is an actin-binding protein with multiple roles in different cell types. In nonmuscle cells, the cytoskeletal isoform is found along microfilament bundles and adherens-type junctions, where it is involved in binding actin to the membrane. In contrast, skeletal, cardiac, and smooth muscle isoforms are localized to the Z-disc and analogous dense bodies, where they help anchor the myofibrillar actin filaments. This gene encodes a muscle-specific, alpha actinin isoform that is expressed in both skeletal and cardiac muscles. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2013]

Actinin Alpha 2

F-actin cross-linking protein which is thought to anchor actin to a variety of intracellular structures. This is a bundling protein.

Actin filament uncapping
Cardiac muscle cell development
Cell adhesion
Focal adhesion assembly
MAPK cascade
Microspike assembly
Muscle filament sliding
Negative regulation of potassium ion transmembrane transporter activity
Negative regulation of potassium ion transport
Negative regulation of protein localization to cell surface
Phospholipase C-activating angiotensin-activated signaling pathway
Platelet degranulation
Positive regulation of cation channel activity
Positive regulation of endocytic recycling
Positive regulation of potassium ion transmembrane transporter activity
Positive regulation of potassium ion transport
Protein localization to plasma membrane
Regulation of apoptotic process
Regulation of membrane potential
Regulation of NMDA receptor activity
Sarcomere organization

Z line. Colocalizes with MYOZ1 and FLNC at the Z-lines of skeletal muscle.

Cardiomyopathy, familial hypertrophic 23, with or without left ventricular non-compaction (CMH23): A hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death.
Cardiomyopathy, dilated 1AA, with or without left ventricular non-compaction (CMD1AA): A disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death.
Myopathy, congenital, with structured cores and Z-line abnormalities (MYOCOZ): An autosomal dominant muscular disorder characterized by progressive early-onset muscle weakness, gait difficulties, loss of ambulation, and respiratory insufficiency. Morphological and ultrastructural analyses of muscle biopsies reveal type 1 fiber predominance, multiple structured cores forming a circular arrangement beneath the sarcolemma, and jagged Z-lines.
Myopathy, distal, 6, adult onset, autosomal dominant (MPD6): An autosomal dominant muscular disorder characterized by adult onset of asymmetric distal muscle weakness, primarily affecting the lower limbs and resulting in gait difficulties. Some patients develop involvement of proximal and upper limb muscles.

Ubiquitinated by FBXL22, leading to proteasomal degradation.