Dystrophin, Rod Domain (DMD) Antibody – Mouse Monoclonal

The dystrophin gene is the largest gene found in nature, measuring 2.4 Mb. The gene was identified through a positional cloning approach, targeted at the isolation of the gene responsible for Duchenne (DMD) and Becker (BMD) Muscular Dystrophies. DMD is a recessive, fatal, X-linked disorder occurring at a frequency of about 1 in 3,500 new-born males. BMD is a milder allelic form. In general, DMD patients carry mutations which cause premature translation termination (nonsense or frame shift mutations), while in BMD patients dystrophin is reduced either in molecular weight (derived from in-frame deletions) or in expression level. The dystrophin gene is highly complex, containing at least eight independent, tissue-specific promoters and two polyA-addition sites. Furthermore, dystrophin RNA is differentially spliced, producing a range of different transcripts, encoding a large set of protein isoforms. Dystrophin (as encoded by the Dp427 transcripts) is a large, rod-like cytoskeletal protein which is found at the inner surface of muscle fibers. Dystrophin is part of the dystrophin-glycoprotein complex (DGC), which bridges the inner cytoskeleton (F-actin) and the extra-cellular matrix. [provided by RefSeq, Jul 2008]

dystrophin: Anchors the extracellular matrix to the cytoskeleton via F-actin. Ligand for dystroglycan. Component of the dystrophin- associated glycoprotein complex which accumulates at the neuromuscular junction (NMJ) and at a variety of synapses in the peripheral and central nervous systems and has a structural function in stabilizing the sarcolemma. Also implicated in signaling events and synaptic transmission. Defects in DMD are the cause of Duchenne muscular dystrophy (DMD). DMD is the most common form of muscular dystrophy; a sex-linked recessive disorder. It typically presents in boys aged 3 to 7 year as proximal muscle weakness causing waddling gait, toe-walking, lordosis, frequent falls, and difficulty in standing up and climbing up stairs. The pelvic girdle is affected first, then the shoulder girdle. Progression is steady and most patients are confined to a wheelchair by age of 10 or 12. Flexion contractures and scoliosis ultimately occur. About 50% of patients have a lower IQ than their genetic expectations would suggest. There is no treatment. Defects in DMD are the cause of Becker muscular dystrophy (BMD). BMD resembles DMD in hereditary and clinical features but is later in onset and more benign. Defects in DMD are a cause of cardiomyopathy dilated X- linked type 3B (CMD3B); also known as X-linked dilated cardiomyopathy (XLCM). Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death. 6 isoforms of the human protein are produced by alternative splicing.

Protein type: Motility/polarity/chemotaxis; Cytoskeletal

Chromosomal Location of Human Ortholog: Xp21.2

Cellular Component: filopodium membrane; cell surface; protein complex; costamere; syntrophin complex; Z disc; cytosol; cell-matrix junction; lipid raft; actin cytoskeleton; dystrophin-associated glycoprotein complex; postsynaptic membrane; cytoskeleton; plasma membrane; synapse; nucleus; lateral plasma membrane; sarcolemma; filopodium

Molecular Function: protein binding; myosin binding; zinc ion binding; structural constituent of cytoskeleton; structural constituent of muscle; nitric-oxide synthase binding; actin binding; vinculin binding

Biological Process: regulation of skeletal muscle contraction via regulation of the release of sequestered calcium ion; muscle maintenance; muscle development; extracellular matrix organization and biogenesis; cellular protein complex assembly; regulation of heart rate; regulation of skeletal muscle contraction; negative regulation of peptidyl-serine phosphorylation; muscle fiber development; positive regulation of neuron differentiation; peptide biosynthetic process; muscle filament sliding; cardiac muscle contraction

Disease: Cardiomyopathy, Dilated, 3b; Muscular Dystrophy, Duchenne Type; Muscular Dystrophy, Becker Type