A possible structural model of members of the CPF family of cuticular proteins implicating binding to components other than chitin

J Insect Physiol. 2010 Oct;56(10):1420-6. doi: 10.1016/j.jinsphys.2010.04.002. Epub 2010 Apr 28.


The physical properties of cuticle are determined by the structure of its two major components, cuticular proteins (CPs) and chitin, and, also, by their interactions. A common consensus region (extended R&R Consensus) found in the majority of cuticular proteins, the CPRs, binds to chitin. Previous work established that beta-pleated sheet predominates in the Consensus region and we proposed that it is responsible for the formation of helicoidal cuticle. Remote sequence similarity between CPRs and a lipocalin, bovine plasma retinol binding protein (RBP), led us to suggest an antiparallel beta-sheet half-barrel structure as the basic folding motif of the R&R Consensus. There are several other families of cuticular proteins. One of the best defined is CPF. Its four members in Anopheles gambiae are expressed during the early stages of either pharate pupal or pharate adult development, suggesting that the proteins contribute to the outer regions of the cuticle, the epi- and/or exo-cuticle. These proteins did not bind to chitin in the same assay used successfully for CPRs. Although CPFs are distinct in sequence from CPRs, the same lipocalin could also be used to derive homology models for one A. gambiae and one Drosophila melanogaster CPF. For the CPFs, the basic folding motif predicted is an eight-stranded, antiparallel beta-sheet, full-barrel structure. Possible implications of this structure are discussed and docking experiments were carried out with one possible Drosophila ligand, 7(Z),11(Z)-heptacosadiene.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aedes / chemistry
  • Aedes / genetics
  • Aedes / metabolism*
  • Amino Acid Sequence
  • Animals
  • Cattle
  • Chitin / chemistry*
  • Chitin / genetics
  • Chitin / metabolism*
  • Drosophila Proteins / chemistry
  • Drosophila Proteins / genetics
  • Drosophila Proteins / metabolism
  • Drosophila melanogaster / chemistry
  • Drosophila melanogaster / genetics
  • Drosophila melanogaster / metabolism*
  • Insect Proteins / chemistry*
  • Insect Proteins / genetics
  • Insect Proteins / metabolism*
  • Models, Molecular
  • Molecular Sequence Data
  • Multigene Family*
  • Protein Binding
  • Protein Structure, Secondary
  • Retinol-Binding Proteins, Plasma / chemistry
  • Retinol-Binding Proteins, Plasma / metabolism
  • Sequence Alignment


  • Drosophila Proteins
  • Insect Proteins
  • Retinol-Binding Proteins, Plasma
  • cuticle proteins, insects
  • Chitin