cDNA cloning of an adult male putative lipocalin specific to tergal gland aphrodisiac secretion in an insect (Leucophaea maderae)

Abstract
Lma‐P22 is a cuticular surface protein specific to the tergal gland secretion of Leucophaea maderae adult males which is ingested by females just before copulation. The complete Lma‐P22 cDNA sequence was determined by RT‐PCR using primers based on Edman degradation fragments. The recombinant protein expressed in Escherichia coli was recognized by an anti‐Lma‐P22 antibody. Northern blot analysis indicates that the corresponding mRNA is transcribed only in the epidermis of male tergites. Sequence analysis indicated that Lma‐P22 deduced protein belongs to the lipocalin family. Lipocalins are extracellular proteins which carry hydrophobic compounds and some of them can bind sexual pheromone in vertebrates. Lma‐P22 is the first example of a lipocalin‐like protein involved in insect sexual behavior.