module: dmel_vacuolar_atpase
title: Vacuolar H+-ATPase in Drosophila melanogaster
label: Vacuolar ATPase
module_type: PROTEIN_COMPLEX
description: >-
  The vacuolar H+-ATPase (V-ATPase) is a rotary proton pump that acidifies
  lysosomes, endosomes, the Golgi and secretory vesicles, and in specialized
  epithelia such as the Malpighian tubules and midgut energizes the plasma
  membrane for transport. The cytosolic V1 domain hydrolyses ATP at three
  catalytic sites in an A3B3 hexamer, and the central rotor (subunits D, F and
  d) transmits rotation to a ring of proteolipid c subunits in the membrane V0
  domain. The V0 a subunit provides the proton path together with the c ring,
  and peripheral stalks of E and G subunits, with C and H, hold the stator.
  Reversible dissociation of V1 from V0 regulates activity. In Drosophila many
  subunits are encoded by paralogous genes, some with tissue- or
  testis-restricted expression, and the accessory proteins Ac45 and ATP6AP2
  associate with V0.
summary: >-
  Rotary proton pump of an ATP-hydrolysing V1 domain and a proton-translocating
  V0 domain, with paralogous subunit genes and V0 accessory proteins.
concepts:
  - {id: GO:0033176, label: proton-transporting V-type ATPase complex}
notes: >-
  Decomposition. Subunits are grouped by domain and by subunit type; each gene
  is its own annoton because paralogs of one subunit type are alternatives
  rather than co-subunits, and which paralogs assemble together in which
  tissue is not mapped. Subunit-type assignments follow the UniProt protein
  names. CG5421 is placed with the accessory subunits as in FlyBase; its
  function is not characterized. The proton-pumping activity belongs to the
  assembled complex; only ATP hydrolysis is attached to the catalytic A
  subunits.
complex: false
parts:
  - id: v1_domain
    label: V1 domain
    role: ATP hydrolysis domain
    concepts:
      - {id: GO:0000221, label: "vacuolar proton-transporting V-type ATPase, V1 domain"}
    parts:
      - id: v1_subunit_a
        label: V1 catalytic subunit A
        role: catalytic A subunit (paralogs)
        genes: [Vha68-1, Vha68-2, Vha68-3]
        function: {id: GO:0016887, label: ATP hydrolysis activity}
      - id: v1_subunit_b
        label: V1 subunit B
        role: non-catalytic B subunit
        genes: [Vha55]
      - id: v1_rotor_and_stator
        label: V1 rotor and stator subunits
        role: central stalk (D, F) and peripheral stalk and regulatory (C, E, G, H) subunits
        genes: [Vha36-1, Vha36-2, Vha36-3, Vha14-1, Vha14-2, CG15719, Vha44, Vha26, Vha13, VhaSFD]
  - id: v0_domain
    label: V0 domain
    role: proton translocation domain
    concepts:
      - {id: GO:0000220, label: "vacuolar proton-transporting V-type ATPase, V0 domain"}
    parts:
      - id: v0_subunit_a
        label: V0 subunit a
        role: a subunit (paralogs)
        genes: [Vha100-1, Vha100-2, Vha100-3, Vha100-4, Vha100-5]
      - id: v0_proteolipid_ring
        label: V0 proteolipid c ring
        role: c and c'' proteolipid subunits
        genes: [Vha16-1, Vha16-2, Vha16-3, Vha16-4, Vha16-5, VhaPPA1-1, VhaPPA1-2]
      - id: v0_subunit_d
        label: V0 subunit d
        role: d subunit (paralogs)
        genes: [VhaAC39-1, VhaAC39-2]
      - id: v0_subunit_e
        label: V0 subunit e
        role: e subunit (paralogs)
        genes: [VhaM9.7-a, VhaM9.7-b, VhaM9.7-c, VhaM9.7-d]
  - id: vatpase_accessory
    label: Accessory subunits
    role: V0-associated accessory proteins
    group: VHA-ACS