To accommodate growth and development, insect must periodically shed its old skeleton and replace it with a new one (molting). After each molt, the newly formed cuticle is soft, flexible, and unable to protect insect from water loss, external physical injuries or pathogens. The newly formed cuticle must go through sclerotization for insects to survive. The primary factor responsible for initiating this process is a neuropeptide called bursicon. Despite the recent identification of bursicon genes in the fruit fly Drosophila melanogaster, little is known about its signal transduction pathway. In the present study, we cloned bursicon a and b genes from the house fly Musca domestica using 3¢ and 5¢ RACE and investigated developmental profiles of bursicon a and b transcripts using PCR and in-situ hybridization. Most importantly, we expressed the recombinant bursicon using Bac-to-Bac baculovirus expression system and demonstrated bursicon activity in neck-ligated fly assay, which leads to identification of a specific set of genes that might be involved in cuticle sclerotization.