1eg4: Difference between revisions

==Disease==

[[http://www.uniprot.org/uniprot/DAG1_HUMAN DAG1_HUMAN]] Defects in DAG1 are the cause of muscular dystrophy-dystroglycanopathy limb-girdle type C7 (MDDGC7) [MIM:[http://omim.org/entry/613818 613818]]. An autosomal recessive muscular dystrophy showing onset in early childhood, and associated with mental retardation without structural brain anomalies. Note=MDDGC7 is caused by DAG1 mutations that interfere with normal post-translational processing, resulting in defective DAG1 glycosylation and impaired interactions with extracellular-matrix components. Other muscular dystrophy-dystroglycanopathies are caused by defects in enzymes involved in protein O-glycosylation.<ref>PMID:21388311</ref> [[http://www.uniprot.org/uniprot/DMD_HUMAN DMD_HUMAN]] Defects in DMD are the cause of Duchenne muscular dystrophy (DMD) [MIM:[http://omim.org/entry/310200 310200]]. 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.<ref>PMID:8401582</ref><ref>PMID:7981690</ref><ref>PMID:8817332</ref><ref>PMID:9851445</ref> Defects in DMD are the cause of Becker muscular dystrophy (BMD) [MIM:[http://omim.org/entry/300376 300376]]. BMD resembles DMD in hereditary and clinical features but is later in onset and more benign.<ref>PMID:10573008</ref> Defects in DMD are a cause of cardiomyopathy dilated X-linked type 3B (CMD3B) [MIM:[http://omim.org/entry/302045 302045]]; 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.<ref>PMID:9170407</ref><ref>PMID:12354438</ref><ref>PMID:12359139</ref>  

==Function==

[[http://www.uniprot.org/uniprot/DAG1_HUMAN DAG1_HUMAN]] The dystroglycan complex is involved in a number of processes including laminin and basement membrane assembly, sarcolemmal stability, cell survival, peripheral nerve myelination, nodal structure, cell migration, and epithelial polarization.<ref>PMID:9851927</ref><ref>PMID:11724572</ref><ref>PMID:16254364</ref><ref>PMID:17360738</ref>  Alpha-dystroglycan is an extracellular peripheral glycoprotein that acts as a receptor for both extracellular matrix proteins containing laminin-G domains, and for certain adenoviruses. Receptor for laminin-2 (LAMA2) and agrin in peripheral nerve Schwann cells. Also acts as a receptor for M.leprae in peripheral nerve Schwann cells but only in the presence of the G-domain of LAMA2, and for lymphocytic choriomeningitis virus, Old World Lassa fever virus, and clade C New World arenaviruses.<ref>PMID:9851927</ref><ref>PMID:11724572</ref><ref>PMID:16254364</ref><ref>PMID:17360738</ref>  Beta-dystroglycan is a transmembrane protein that plays important roles in connecting the extracellular matrix to the cytoskeleton. Acts as a cell adhesion receptor in both muscle and non-muscle tissues. Receptor for both DMD and UTRN and, through these interactions, scaffolds axin to the cytoskeleton. Also functions in cell adhesion-mediated signaling and implicated in cell polarity.<ref>PMID:9851927</ref><ref>PMID:11724572</ref><ref>PMID:16254364</ref><ref>PMID:17360738</ref> [[http://www.uniprot.org/uniprot/DMD_HUMAN DMD_HUMAN]] 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.<ref>PMID:16710609</ref>

 

==About this Structure==

[[1eg4]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1EG4 OCA].

 

==Reference==

<ref group="xtra">PMID:010932245</ref><references group="xtra"/><references/>

[[Category: Eck, M J.]]

[[Category: Huang, X.]]

[[Category: Joachimiak, A.]]

[[Category: Poy, F.]]

[[Category: Sudol, M.]]

[[Category: Zhang, R.]]

[[Category: Ww domain]]