Desmin is a protein that in humans is encoded by the DES gene. Desmin is a muscle-specific, type III intermediate filament that integrates the sarcolemma, Z disk, and nuclear membrane in sarcomeres and regulates sarcomere architecture.
Desmoplakin is a protein in humans that is encoded by the DSP gene. Desmoplakin is a critical component of desmosome structures in cardiac muscle and epidermal cells, which function to maintain the structural integrity at adjacent cell contacts. In cardiac muscle, desmoplakin is localized to intercalated discs which mechanically couple cardiac cells to function in a coordinated syncytial structure. Mutations in desmoplakin have been shown to play a role in dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy, where it may present with acute myocardial injury; striate palmoplantar keratoderma, Carvajal syndrome and paraneoplastic pemphigus.
Plakoglobin, also known as junction plakoglobin or gamma-catenin, is a protein that in humans is encoded by the JUP gene. Plakoglobin is a member of the catenin protein family and homologous to β-catenin. Plakoglobin is a cytoplasmic component of desmosomes and adherens junctions structures located within intercalated discs of cardiac muscle that function to anchor sarcomeres and join adjacent cells in cardiac muscle. Mutations in plakoglobin are associated with arrhythmogenic right ventricular dysplasia.
Nebulette is a cardiac-specific isoform belonging to the nebulin family of proteins. It is encoded by the NEBL gene. This family is composed of 5 members: nebulette, nebulin, N-RAP, LASP-1 and LASP-2. Nebulette localizes to Z-discs of cardiac muscle and appears to regulate the length of actin thin filaments.
Alpha-actinin-1 is a protein that in humans is encoded by the ACTN1 gene.
ACTC1 encodes cardiac muscle alpha actin. This isoform differs from the alpha actin that is expressed in skeletal muscle, ACTA1. Alpha cardiac actin is the major protein of the thin filament in cardiac sarcomeres, which are responsible for muscle contraction and generation of force to support the pump function of the heart.
Alpha II-spectrin, also known as Spectrin alpha chain, brain is a protein that in humans is encoded by the SPTAN1 gene. Alpha II-spectrin is expressed in a variety of tissues, and is highly expressed in cardiac muscle at Z-disc structures, costameres and at the sarcolemma membrane. Mutations in alpha II-spectrin have been associated with early infantile epileptic encephalopathy-5, and alpha II-spectrin may be a valuable biomarker for Guillain–Barré syndrome and infantile congenital heart disease.
Alpha-actinin-2 is a protein which in humans is encoded by the ACTN2 gene. This gene encodes an alpha-actinin isoform that is expressed in both skeletal and cardiac muscles and functions to anchor myofibrillar actin thin filaments and titin to Z-discs.
Coxsackievirus and adenovirus receptor (CAR) is a protein that in humans is encoded by the CXADR gene. The protein encoded by this gene is a type I membrane receptor for group B coxsackie viruses and subgroup C adenoviruses. CAR protein is expressed in several tissues, including heart, brain, and, more generally, epithelial and endothelial cells. In cardiac muscle, CAR is localized to intercalated disc structures, which electrically and mechanically couple adjacent cardiomyocytes. CAR plays an important role in the pathogenesis of myocarditis, dilated cardiomyopathy, and in arrhythmia susceptibility following myocardial infarction or myocardial ischemia. In addition, an isoform of CAR (CAR-SIV) has been recently identified in the cytoplasm of pancreatic beta cells. It's been suggested that CAR-SIV resides in the insulin secreting granules and might be involved in the virus infection of these cells.
Alpha-actinin-4 is a protein that in humans is encoded by the ACTN4 gene.
PDZ and LIM domain protein 5 is a protein that in humans is encoded by the PDLIM5 gene.
Myosin essential light chain (ELC), ventricular/cardiac isoform is a protein that in humans is encoded by the MYL3 gene. This cardiac ventricular/slow skeletal ELC isoform is distinct from that expressed in fast skeletal muscle (MYL1) and cardiac atrial muscle (MYL4). Ventricular ELC is part of the myosin molecule and is important in modulating cardiac muscle contraction.
PDZ and LIM domain protein 1 is a protein that in humans is encoded by the PDLIM1 gene.
Nebulin-related-anchoring protein(N-RAP) is a protein that in humans is encoded by the NRAP gene. N-RAP is a muscle-specific isoform belonging to the nebulin family of proteins. This family is composed of 5 members: N-RAP, nebulin, nebulette, LASP-1 and LASP-2. N-RAP is involved in both myofibrillar myogenesis during development and cell-cell connections in mature muscle.
Cysteine and glycine-rich protein 3 also known as cardiac LIM protein (CLP) or muscle LIM protein (MLP) is a protein that in humans is encoded by the CSRP3 gene.
PDZ and LIM domain protein 4 is a protein that in humans is encoded by the PDLIM4 gene.
Myozenin-2, also referred to as Calsarcin-1, is a protein that in humans is encoded by the MYOZ2 gene. The Calsarcin-1 isoform is a muscle protein expressed in cardiac muscle and slow-twitch skeletal muscle, which functions to tether calcineurin to alpha-actinin at Z-discs, and inhibit the pathological cardiac hypertrophic response. This differs from the fast-skeletal muscle isoform, calsarcin-2.
LIM domain binding 3 (LDB3), also known as Z-band alternatively spliced PDZ-motif (ZASP), is a protein which in humans is encoded by the LDB3 gene. ZASP belongs to the Enigma subfamily of proteins and stabilizes the sarcomere during contraction, through interactions with actin in cardiac and skeletal muscles. Mutations in the ZASP gene has been associated with several muscular diseases.
Myopodin protein, also called Synaptopodin-2 is a protein that in humans is encoded by the SYNPO2 gene. Myopodin is expressed in cardiac, smooth muscle and skeletal muscle, and localizes to Z-disc structures.
Myozenin-1 is a protein that in humans is encoded by the MYOZ1 gene.
