Biochemical characterization of cuticular proteins from the red flour beetle, Tribolium castaneum

Cuticular proteins from the red flour beetle, Tribolium castaneum were analysed by qualitative and quantitative biochemical analyses. The abilities of different agents to extract proteins from mass-prepared cuticles were examined. One percent sodium dodecyl sulfate, 7M urea, and 8M guanidine extracted between 35-40% of the total weight of the cuticle. Water and 1% Triton X-100 extracted approximately 15% of the total weight of the cuticle. NaOH extracted approximately 80% of the total weight of the cuticle. Sodium dodecyl sulfate (1%) was the most effective solvent for extracting cuticular proteins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to examine the sodium dodecyl sulfate-soluble cuticular proteins of hand-dissected larval, pupal, and adult cuticles. The larval and pupal cuticular proteins were qualitatively similar by this analysis and were distinct from the adult cuticular proteins. (Abstract shortened by UMI.).