From Wikipedia, the free encyclopedia
Jump to: navigation, search
Myosin, heavy chain 11, smooth muscle
Protein MYH11 PDB 1br1.png
PDB rendering based on 1br1.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols MYH11 ; AAT4; FAA4; SMHC; SMMHC
External IDs OMIM160745 MGI102643 HomoloGene128512 GeneCards: MYH11 Gene
RNA expression pattern
PBB GE MYH11 201496 x at tn.png
PBB GE MYH11 201495 x at tn.png
PBB GE MYH11 201497 x at tn.png
More reference expression data
Species Human Mouse
Entrez 4629 17880
Ensembl ENSG00000133392 ENSMUSG00000018830
UniProt P35749 O08638
RefSeq (mRNA) NM_001040113 NM_001161775
RefSeq (protein) NP_001035202 NP_001155247
Location (UCSC) Chr 16:
15.8 – 15.95 Mb
Chr 16:
14.19 – 14.29 Mb
PubMed search [1] [2]

Myosin-11 is a protein that in humans is encoded by the MYH11 gene.[1][2]


Myosin-11 is a smooth muscle myosin belonging to the myosin heavy chain family. Myosin-11 is a subunit of a hexameric protein that consists of two heavy chain subunits and two pairs of non-identical light chain subunits.

It is a major contractile protein, converting chemical energy into mechanical energy through the hydrolysis of ATP.

Alternative splicing generates isoforms that are differentially expressed, with ratios changing during muscle cell maturation.[2]

Clinical significance[edit]

Thoracic aortic aneurysms leading to acute aortic dissections (TAAD) can be inherited in isolation or in association with genetic syndromes, such as Marfan syndrome and Loeys-Dietz syndrome. When TAAD occurs in the absence of syndromic features, it is inherited in an autosomal dominant manner with decreased penetrance and variable expression, the disease is referred to as familial TAAD. Familial TAAD exhibits significant clinical and genetic heterogeneity. Mutations in MYH11 have been described in individuals with TAAD with patent ductus arteriosus (PDA). Of individuals with TAAD, approximately 4% have mutations in TGFBR2, and approximately 1-2% have mutations in either TGFBR1 or MYH11. In addition, FBN1 mutations have also been reported in individuals with TAAD. Mutations within the SMAD3 gene have recently been reported in patients with a syndromic form of aortic aneurysms and dissections with early onset osteoarthritis. SMAD3 mutations are thought to account for approximately 2% of familial TAAD. Additionally, mutations in the ACTA2 gene are thought to account for approximately 10-14% of familial TAAD.[3]

Acute myeloid leukemia[edit]

The gene encoding a human ortholog of rat NUDE1 is transcribed from the reverse strand of this gene, and its 3' end overlaps with that of the latter. The pericentric inversion of chromosome 16 [inv(16)(p13q22)] produces a chimeric transcript that encodes a protein consisting of the first 165 residues from the N-terminus of core-binding factor beta in a fusion with the C-terminal portion of the smooth muscle myosin heavy chain. This chromosomal rearrangement is associated with acute myeloid leukemia of the M4Eo subtype.

Intestinal cancer[edit]

MYH11 mutations appear to contribute to human intestinal cancer.[4]

External links[edit]


  1. ^ Matsuoka R, Yoshida MC, Furutani Y, Imamura S, Kanda N, Yanagisawa M, Masaki T, Takao A (Jun 1993). "Human smooth muscle myosin heavy chain gene mapped to chromosomal region 16q12". Am J Med Genet 46 (1): 61–7. doi:10.1002/ajmg.1320460110. PMID 7684189. 
  2. ^ a b "Entrez Gene: MYH11 myosin, heavy chain 11, smooth muscle". 
  3. ^ Boston University Center for Human Genetics - Aortic Aneurysms
  4. ^ Alhopuro P, Phichith D, Tuupanen S, Sammalkorpi H, Nybondas M, Saharinen J, Robinson JP, Yang Z, Chen LQ, Orntoft T, Mecklin JP, Järvinen H, Eng C, Moeslein G, Shibata D, Houlston RS, Lucassen A, Tomlinson IP, Launonen V, Ristimäki A, Arango D, Karhu A, Sweeney HL, Aaltonen LA (April 2008). "Unregulated smooth-muscle myosin in human intestinal neoplasia". Proc. Natl. Acad. Sci. U.S.A. 105 (14): 5513–8. doi:10.1073/pnas.0801213105. PMC 2291082. PMID 18391202. 

Further reading[edit]