Dystrophin

Dystrophin (muscular dystrophy, Duchenne and Becker types)
PDB rendering based on 1dxx.
Available structures PDB Ortholog search: Template:Homologene2PDBe PDBe, Template:Homologene2uniprot RCSB List of PDB id codes 1dxx​, 1eg3​, 1eg4​
Identifiers
Symbols	DMD ; BMD; CMD3B; DXS142; DXS164; DXS206; DXS230; DXS239; DXS268; DXS269; DXS270; DXS272
External IDs	Template:OMIM5 Template:MGI HomoloGene: 20856
Gene ontology Molecular function Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Cellular component Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO Biological process Template:GNF GO Template:GNF GO Template:GNF GO Template:GNF GO
RNA expression pattern
More reference expression data
Orthologs
Template:GNF Ortholog box
Species	Human	Mouse
Entrez	n/a	n/a
Ensembl	n/a	n/a
UniProt	n/a	n/a
RefSeq (mRNA)	n/a	n/a
RefSeq (protein)	n/a	n/a
Location (UCSC)	n/a	n/a
PubMed search	n/a	n/a

Dystrophin is a rod-shaped cytoplasmic protein, and a vital part of a protein complex that connects the cytoskeleton of a muscle fiber to the surrounding extracellular matrix through the cell membrane. This complex is variously known as the costamere or the dystrophin-associated protein complex. Many muscle proteins, such as α-dystrobrevin, syncoilin, synemin, sarcoglycan, dystroglycan, and sarcospan, colocalize with dystrophin at the costamere.

As of 2007 dystrophin has the longest gene known, at locus Xp21. The primary transcript measures 2.4 megabases (thus the gene comprises 0.008% of the human genome), and takes 16 hours to transcribe. The 79 exons code for a protein of over 3500 amino acid residues.

Pathology

Its deficiency is one of the root causes of muscular dystrophy. It was first identified in 1987 by Louis M. Kunkel , after the 1986 discovery of the mutated gene that causes Duchenne muscular dystrophy (DMD) .

Normal tissue contains small amounts of dystrophin (about 0.002% of total muscle protein), but its absence leads to both DMD and fibrosis, a condition of muscle hardening. A different mutation of the same gene causes defective dystrophin, leading to Becker's muscular dystrophy (BMD).

Further reading

• Roberts RG, Gardner RJ, Bobrow M (1994). "Searching for the 1 in 2,400,000: a review of dystrophin gene point mutations". Hum. Mutat. 4 (1): 1–11. doi:10.1002/humu.1380040102. PMID 7951253.CS1 maint: Multiple names: authors list (link)
• Tinsley JM, Blake DJ, Zuellig RA, Davies KE (1994). "Increasing complexity of the dystrophin-associated protein complex". Proc. Natl. Acad. Sci. U.S.A. 91 (18): 8307–13. PMID 8078878.CS1 maint: Multiple names: authors list (link)
• Blake DJ, Weir A, Newey SE, Davies KE (2002). "Function and genetics of dystrophin and dystrophin-related proteins in muscle". Physiol. Rev. 82 (2): 291–329. doi:10.1152/physrev.00028.2001. PMID 11917091.CS1 maint: Multiple names: authors list (link)
• Röper K, Gregory SL, Brown NH (2003). "The 'spectraplakins': cytoskeletal giants with characteristics of both spectrin and plakin families". J. Cell. Sci. 115 (Pt 22): 4215–25. PMID 12376554.CS1 maint: Multiple names: authors list (link)
• Muntoni F, Torelli S, Ferlini A (2003). "Dystrophin and mutations: one gene, several proteins, multiple phenotypes". Lancet neurology. 2 (12): 731–40. PMID 14636778.CS1 maint: Multiple names: authors list (link)
• Haenggi T, Fritschy JM (2006). "Role of dystrophin and utrophin for assembly and function of the dystrophin glycoprotein complex in non-muscle tissue". Cell. Mol. Life Sci. 63 (14): 1614–31. doi:10.1007/s00018-005-5461-0. PMID 16710609.

External links

• Dystrophin at the US National Library of Medicine Medical Subject Headings (MeSH)