module: dmel_dystrophin_glycoprotein_complex
title: Dystrophin glycoprotein complex in Drosophila melanogaster
label: Dystrophin glycoprotein complex
module_type: PROTEIN_COMPLEX
description: >-
  The dystrophin glycoprotein complex (DGC) links the actin cytoskeleton to the
  extracellular matrix across the plasma membrane, mainly in muscle. Dystroglycan
  (Dg) spans the membrane: its extracellular part binds laminin and other matrix
  proteins and its cytoplasmic tail binds dystrophin, which in turn binds actin.
  Sarcoglycans form a transmembrane subcomplex that stabilizes the link, and the
  cytoplasmic adaptors dystrobrevin and syntrophins bind dystrophin and recruit
  signaling proteins. Drosophila has single dystrophin (Dys) and dystroglycan genes,
  one dystrobrevin, three sarcoglycans and two syntrophin-like genes. Loss of Dys or
  Dg causes age-dependent muscle degeneration, and Dg also acts in epithelial
  polarity and in the oocyte.
summary: >-
  Dystroglycan, dystrophin, dystrobrevin, sarcoglycans and syntrophins linking actin
  to the extracellular matrix.
concepts:
  - {id: GO:0016010, label: dystrophin-associated glycoprotein complex}
parts:
  - id: dystroglycan
    label: Dystroglycan
    role: transmembrane matrix receptor
    description: >-
      Single Dg gene encoding the alpha and beta dystroglycan chains, which form the
      dystroglycan complex.
    genes: [Dg]
    function: {id: GO:0005055, label: laminin receptor activity}
  - id: dystrophin_and_dystrobrevin
    label: Dystrophin and dystrobrevin
    role: cytoplasmic actin linker and adaptor
    group: DYS-REL
    complex: false
  - id: sarcoglycans
    label: Sarcoglycan complex
    role: transmembrane stabilizing subcomplex
    group: SCG
    complex_term: {id: GO:0016012, label: sarcoglycan complex}
  - id: syntrophins
    label: Syntrophins
    role: cytoplasmic adaptors
    group: SYN
    complex: false
connections:
  - source: dystroglycan
    target: dystrophin_and_dystrobrevin
    connection_type: PROVIDES_INPUT_FOR
    description: >-
      The cytoplasmic tail of dystroglycan binds dystrophin, linking the matrix to
      actin.
notes: >-
  Extracellular ligands (laminins, perlecan) and dystroglycan glycosylation enzymes
  are context, not parts. Syntrophins and dystrophin/dystrobrevin are modelled per
  gene because their assembly into stable subcomplexes has not been shown in
  Drosophila. Dystroglycan is given laminin receptor activity (GO:0005055;
  GOA IDA, IBA). The other subunits carry structural or binding terms only
  (structural constituent of muscle by NAS, actin filament binding,
  WW domain binding) and are left without an annoton function.
groups: [DGC, SYN, DYS-REL, SCG]