module: dmel_exocyst
title: Exocyst complex in Drosophila melanogaster
label: Exocyst
module_type: PROTEIN_COMPLEX
description: >-
  The exocyst is an octameric tethering complex that captures secretory and
  recycling vesicles at sites of exocytosis on the plasma membrane before
  SNARE-mediated fusion. Its eight subunits (Sec3, Sec5, Sec6, Sec8, Sec10,
  Sec15, Exo70 and Exo84) are long helical-bundle proteins; Sec3 and Exo70 bind
  plasma membrane phosphoinositides and small GTPases, while Sec15 binds Rab11
  on the vesicle. Structural studies divide the complex into two four-subunit
  modules, Sec3-Sec5-Sec6-Sec8 and Sec10-Sec15-Exo70-Exo84. In Drosophila the
  exocyst is required for polarized membrane delivery, for example to the
  rhabdomere of photoreceptors, to growing neurites and for epithelial
  junction protein trafficking.
summary: >-
  Octameric complex that tethers secretory and recycling vesicles to the
  plasma membrane for exocytosis.
concepts:
  - {id: GO:0000145, label: exocyst}
notes: >-
  Boundary. The module contains the eight exocyst subunits. Rab11, Ral and
  Rho-family GTPases that bind exocyst subunits, and the SNAREs that complete
  fusion, are partners, not parts. The two-subcomplex decomposition follows
  the structural organization described for yeast and mammalian exocyst.
  Vesicle membrane tethering activity (GO:7770062), which Sec8, Sec10 and
  Sec15 carry in GOA by IC and the other subunits by NAS, belongs to the
  assembled octamer and is recorded on a complex-level annoton with all eight
  subunits as active units.
complex_term: {id: GO:0000145, label: exocyst}
complex_function:
  function: {id: GO:7770062, label: vesicle membrane tethering activity}
  processes:
    - {id: GO:0006887, label: exocytosis}
  role_description: >-
    Tethers secretory vesicles to the plasma membrane at sites of exocytosis
    before SNARE-mediated fusion.
parts:
  - id: exocyst_subcomplex_1
    label: Exocyst subcomplex I
    role: Sec3-Sec5-Sec6-Sec8 module
    genes: [Sec3, Sec5, Sec6, Sec8]
    processes:
      - {id: GO:0006887, label: exocytosis}
  - id: exocyst_subcomplex_2
    label: Exocyst subcomplex II
    role: Sec10-Sec15-Exo70-Exo84 module
    genes: [Sec10, Sec15, Exo70, Exo84]
    processes:
      - {id: GO:0006887, label: exocytosis}