Precursor De13.1 from Conus delessertii defines the novel G gene superfamily

Peptides. 2013 Mar;41:17-20. doi: 10.1016/j.peptides.2013.01.009. Epub 2013 Jan 20.

Abstract

Peptide de13a was previously purified from the venom of the worm-hunting cone snail Conus delessertii from the Yucatán Channel, México. This peptide has eight cysteine (Cys) residues in the unique arrangement C-C-C-CC-C-C-C, which defines the cysteine framework XIII ("-" represents one or more non-Cys residues). Remarkably, δ-hydroxy-lysine residues have been found only in conotoxin de13a, which also contains an unusually high proportion of hydroxylated amino acid residues. Here, we report the cDNA cloning of the complete precursor De13.1 of a related peptide, de13b, which has the same Cys framework and inter-Cys spacings as peptide de13a, and shares high protein/nucleic acid sequence identity (87%/90%) with de13a, suggesting that both peptides belong to the same conotoxin gene superfamily. Analysis of the signal peptide of precursor De13.1 reveals that this precursor belongs to a novel conotoxin gene superfamily that we chose to name gene superfamily G. Thus far superfamily G only includes two peptides, each of which contains the same, distinctive Cys framework and a high proportion of amino acid residues with hydroxylated side chains.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cloning, Molecular
  • Conotoxins / chemistry
  • Conotoxins / genetics*
  • Conus Snail / genetics*
  • Molecular Sequence Data
  • Open Reading Frames
  • Protein Precursors / chemistry
  • Protein Precursors / genetics*
  • Sequence Analysis, DNA

Substances

  • Conotoxins
  • Protein Precursors