2kkq

Structural highlights

Disease

[MYOTI_HUMAN] Defects in MYOT are the cause of limb-girdle muscular dystrophy type 1A (LGMD1A) [MIM:159000]. LGMD1A is an autosomal dominant degenerative myopathy with onset within a mean age of 28 years. LGMD1A is characterized by progressive skeletal muscle weakness of the hip and shoulder girdles, later progressing to include distal weakness, as well as a distinctive dysarthric pattern of speech. Affected muscle exhibits disorganization and streaming of the Z-line.^{[1] [2]} Defects in MYOT are the cause of myopathy myofibrillar type 3 (MFM3) [MIM:609200]. A neuromuscular disorder characterized by progressive skeletal muscle weakness greater distally than proximally, tight heel cords, hyporeflexia, cardiomyopathy and peripheral neuropathy in some patients. Affected muscle exhibits disorganization and streaming of the Z-line, presence of large hyaline structures, excessive accumulation of myotilin and other ectopically expressed proteins and prominent congophilic deposits.^[3] Defects in MYOT are the cause of spheroid body myopathy (SBM) [MIM:182920]. SBM is an autosomal dominant form of myofibrillar myopathy (MFM), characterized by slowly progressing proximal muscle weakness and dysarthric nasal speech. There is no evidence of cardiomyopathy. Muscle biopsy shows spheroid bodies within the type I muscle fibers.^[4]

Function

[MYOTI_HUMAN] Component of a complex of multiple actin cross-linking proteins. Involved in the control of myofibril assembly and stability at the Z lines in muscle cells.^[5]

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

• Myotilin

References

1. ↑ Hauser MA, Horrigan SK, Salmikangas P, Torian UM, Viles KD, Dancel R, Tim RW, Taivainen A, Bartoloni L, Gilchrist JM, Stajich JM, Gaskell PC, Gilbert JR, Vance JM, Pericak-Vance MA, Carpen O, Westbrook CA, Speer MC. Myotilin is mutated in limb girdle muscular dystrophy 1A. Hum Mol Genet. 2000 Sep 1;9(14):2141-7. PMID:10958653
2. ↑ Hauser MA, Conde CB, Kowaljow V, Zeppa G, Taratuto AL, Torian UM, Vance J, Pericak-Vance MA, Speer MC, Rosa AL. myotilin Mutation found in second pedigree with LGMD1A. Am J Hum Genet. 2002 Dec;71(6):1428-32. Epub 2002 Nov 11. PMID:12428213 doi:10.1086/344532
3. ↑ Selcen D, Engel AG. Mutations in myotilin cause myofibrillar myopathy. Neurology. 2004 Apr 27;62(8):1363-71. PMID:15111675
4. ↑ Foroud T, Pankratz N, Batchman AP, Pauciulo MW, Vidal R, Miravalle L, Goebel HH, Cushman LJ, Azzarelli B, Horak H, Farlow M, Nichols WC. A mutation in myotilin causes spheroid body myopathy. Neurology. 2005 Dec 27;65(12):1936-40. PMID:16380616 doi:10.1212/01.wnl.0000188872.28149.9a
5. ↑ Salmikangas P, van der Ven PF, Lalowski M, Taivainen A, Zhao F, Suila H, Schroder R, Lappalainen P, Furst DO, Carpen O. Myotilin, the limb-girdle muscular dystrophy 1A (LGMD1A) protein, cross-links actin filaments and controls sarcomere assembly. Hum Mol Genet. 2003 Jan 15;12(2):189-203. PMID:12499399