Sequence analysis and expression of a mRNA for a larval-specific cuticular protein, LCP1, from Helicoverpa armigera.

Several cDNA clones for a larval cuticular protein from Helicoverpa armigera were isolated and sequenced. The cDNA clones contain an open reading frame encoding a 109 residue protein which is homologous to other known cuticular proteins. The predicted protein appears to have a signal peptide which would be removed to give a mature protein of 91 amino acid residues with an Mr of 10 127. The mature protein, LCP1 (Larval Cuticular Protein), would be highly acidic, as is found for other cuticular proteins from flexible insect cuticles. The mRNA appears to be expressed throughout larval development although it is more highly expressed in the integument of the late final instar.