8uf4

Structural highlights

Disease

DAG1_HUMAN Defects in DAG1 are the cause of muscular dystrophy-dystroglycanopathy limb-girdle type C7 (MDDGC7) [MIM: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.^[1]

Function

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.^{[2] [3] [4] [5]} 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.^{[6] [7] [8] [9]} 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.^{[10] [11] [12] [13]}

References

1. ↑ Hara Y, Balci-Hayta B, Yoshida-Moriguchi T, Kanagawa M, Beltran-Valero de Bernabe D, Gundesli H, Willer T, Satz JS, Crawford RW, Burden SJ, Kunz S, Oldstone MB, Accardi A, Talim B, Muntoni F, Topaloglu H, Dincer P, Campbell KP. A dystroglycan mutation associated with limb-girdle muscular dystrophy. N Engl J Med. 2011 Mar 10;364(10):939-46. doi: 10.1056/NEJMoa1006939. PMID:21388311 doi:10.1056/NEJMoa1006939
2. ↑ Rambukkana A, Yamada H, Zanazzi G, Mathus T, Salzer JL, Yurchenco PD, Campbell KP, Fischetti VA. Role of alpha-dystroglycan as a Schwann cell receptor for Mycobacterium leprae. Science. 1998 Dec 11;282(5396):2076-9. PMID:9851927
3. ↑ Sotgia F, Lee H, Bedford MT, Petrucci T, Sudol M, Lisanti MP. Tyrosine phosphorylation of beta-dystroglycan at its WW domain binding motif, PPxY, recruits SH2 domain containing proteins. Biochemistry. 2001 Dec 4;40(48):14585-92. PMID:11724572
4. ↑ Imperiali M, Thoma C, Pavoni E, Brancaccio A, Callewaert N, Oxenius A. O Mannosylation of alpha-dystroglycan is essential for lymphocytic choriomeningitis virus receptor function. J Virol. 2005 Nov;79(22):14297-308. PMID:16254364 doi:10.1128/JVI.79.22.14297-14308.2005
5. ↑ Rojek JM, Spiropoulou CF, Campbell KP, Kunz S. Old World and clade C New World arenaviruses mimic the molecular mechanism of receptor recognition used by alpha-dystroglycan's host-derived ligands. J Virol. 2007 Jun;81(11):5685-95. Epub 2007 Mar 14. PMID:17360738 doi:10.1128/JVI.02574-06
6. ↑ Rambukkana A, Yamada H, Zanazzi G, Mathus T, Salzer JL, Yurchenco PD, Campbell KP, Fischetti VA. Role of alpha-dystroglycan as a Schwann cell receptor for Mycobacterium leprae. Science. 1998 Dec 11;282(5396):2076-9. PMID:9851927
7. ↑ Sotgia F, Lee H, Bedford MT, Petrucci T, Sudol M, Lisanti MP. Tyrosine phosphorylation of beta-dystroglycan at its WW domain binding motif, PPxY, recruits SH2 domain containing proteins. Biochemistry. 2001 Dec 4;40(48):14585-92. PMID:11724572
8. ↑ Imperiali M, Thoma C, Pavoni E, Brancaccio A, Callewaert N, Oxenius A. O Mannosylation of alpha-dystroglycan is essential for lymphocytic choriomeningitis virus receptor function. J Virol. 2005 Nov;79(22):14297-308. PMID:16254364 doi:10.1128/JVI.79.22.14297-14308.2005
9. ↑ Rojek JM, Spiropoulou CF, Campbell KP, Kunz S. Old World and clade C New World arenaviruses mimic the molecular mechanism of receptor recognition used by alpha-dystroglycan's host-derived ligands. J Virol. 2007 Jun;81(11):5685-95. Epub 2007 Mar 14. PMID:17360738 doi:10.1128/JVI.02574-06
10. ↑ Rambukkana A, Yamada H, Zanazzi G, Mathus T, Salzer JL, Yurchenco PD, Campbell KP, Fischetti VA. Role of alpha-dystroglycan as a Schwann cell receptor for Mycobacterium leprae. Science. 1998 Dec 11;282(5396):2076-9. PMID:9851927
11. ↑ Sotgia F, Lee H, Bedford MT, Petrucci T, Sudol M, Lisanti MP. Tyrosine phosphorylation of beta-dystroglycan at its WW domain binding motif, PPxY, recruits SH2 domain containing proteins. Biochemistry. 2001 Dec 4;40(48):14585-92. PMID:11724572
12. ↑ Imperiali M, Thoma C, Pavoni E, Brancaccio A, Callewaert N, Oxenius A. O Mannosylation of alpha-dystroglycan is essential for lymphocytic choriomeningitis virus receptor function. J Virol. 2005 Nov;79(22):14297-308. PMID:16254364 doi:10.1128/JVI.79.22.14297-14308.2005
13. ↑ Rojek JM, Spiropoulou CF, Campbell KP, Kunz S. Old World and clade C New World arenaviruses mimic the molecular mechanism of receptor recognition used by alpha-dystroglycan's host-derived ligands. J Virol. 2007 Jun;81(11):5685-95. Epub 2007 Mar 14. PMID:17360738 doi:10.1128/JVI.02574-06