module: dmel_intraflagellar_transport
title: Intraflagellar transport complexes A and B in Drosophila melanogaster
label: Intraflagellar transport
module_type: PROTEIN_COMPLEX
description: >-
  Intraflagellar transport (IFT) moves protein cargo along the axoneme between the
  ciliary base and tip. IFT trains are built from two multi-subunit complexes: IFT-B,
  which is carried toward the tip by kinesin-2 and is required for anterograde
  transport and axoneme assembly, and IFT-A, which is needed mainly for retrograde
  transport by cytoplasmic dynein 2 and for import of membrane proteins. In
  Drosophila, cilia occur only on type I sensory neurons and on sperm. IFT is
  required to build the sensory cilia of chordotonal and external sensory neurons,
  and mutants such as nompB (IFT88) lack mechanosensory potentials, whereas most of
  the sperm axoneme is assembled without IFT.
summary: >-
  IFT-A and IFT-B complexes that move cargo along sensory neuron cilia and are
  required to assemble them.
concepts:
  - {id: GO:0030990, label: intraciliary transport particle}
parts:
  - id: ift_b
    label: IFT-B complex
    role: anterograde IFT and axoneme assembly
    group: IFT-B
    complex_term: {id: GO:0030992, label: intraciliary transport particle B}
    processes:
      - {id: GO:0042073, label: intraciliary transport}
  - id: ift_a
    label: IFT-A complex
    role: retrograde IFT and membrane protein import
    group: IFT-A
    complex_term: {id: GO:0030991, label: intraciliary transport particle A}
    processes:
      - {id: GO:0042073, label: intraciliary transport}
connections:
  - source: ift_b
    target: ift_a
    connection_type: PROVIDES_INPUT_FOR
    description: >-
      IFT-B and IFT-A assemble together into trains; IFT-A is carried to the tip
      with IFT-B and returns with retrograde trains.
notes: >-
  The BBSome subgroup (BBS) of the FlyBase IFT group is already covered by the
  existing bbsome module and is not repeated here. IFT-B is not split into its
  IFT-B1 and IFT-B2 subcomplexes because not all Drosophila members have been
  mapped to them. Kinesin-2 and cytoplasmic dynein 2 motors (see
  dmel_cytoplasmic_dynein_dynactin) are context, not parts.
groups: [IFT-A, IFT-B]
function_note: >-
  No molecular function is assigned: IFT-A and IFT-B are adaptor and scaffold
  complexes that link ciliary cargo to kinesin-2 and dynein-2 motors, and most
  Drosophila IFT subunits have only ND molecular function annotations in GOA.