A multivalent PDZ-domain protein assembles signalling complexes in a G-protein-coupled cascade

Nature. 1997 Jul 17;388(6639):243-9. doi: 10.1038/40805.


How are signalling molecules organized into different pathways within the same cell? In Drosophila, the inaD gene encodes a protein consisting of five PDZ domains which serves as a scaffold to assemble different components of the phototransduction cascade, including the principal light-activated ion channels, the effector phospholipase C-beta and protein kinase C. Null inaD mutants have a dramatically reorganized subcellular distribution of signalling molecules, and a total loss of transduction complexes. Also, mutants defective in a single PDZ domain produce signalling complexes that lack the target protein and display corresponding defects in their physiology. A picture emerges of a highly organized unit of signalling, a 'transduclisome', with PDZ domains functioning as key elements in the organization of transduction complexes in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Binding Sites
  • Calcium Channels / metabolism
  • Drosophila
  • Drosophila Proteins*
  • Electrophysiology
  • Eye Proteins / chemistry
  • Eye Proteins / genetics
  • Eye Proteins / metabolism*
  • Female
  • GTP-Binding Proteins / metabolism*
  • Insect Proteins / metabolism
  • Male
  • Molecular Sequence Data
  • Mutation
  • Photoreceptor Cells, Invertebrate / metabolism
  • Photoreceptor Cells, Invertebrate / ultrastructure
  • Protein Kinase C / metabolism
  • Sequence Homology, Amino Acid
  • Signal Transduction*
  • Transient Receptor Potential Channels
  • Type C Phospholipases / metabolism
  • Vision, Ocular


  • Calcium Channels
  • Drosophila Proteins
  • Eye Proteins
  • Insect Proteins
  • Transient Receptor Potential Channels
  • inaD protein, Drosophila
  • trp protein, Drosophila
  • Protein Kinase C
  • Type C Phospholipases
  • GTP-Binding Proteins