EXPRESSION CLONING AND CHARACTERIZATION OF A PUPAL CUTICLE PROTEIN CDNA OF GALLERIA-MELLONELLA L

Epidermal mRNA of freshly ecdysed pupae of Galleria mellonella was use d to establish a cDNA library in phage lambda gt11. A cDNA clone was i solated by means of a pupal cuticle protein (PCP) specific antibody. N ucleic acid sequence data show an insert of 1212 bp with an open readi ng frame of 1062 bp. The presence of start, stop, and polyadenylation sites suggests, that this insert represents a full length transcript. Conceptual translation resulted in a protein of 353 amino acids includ ing a signal peptide. The final processed protein product is rich in a lanine and charged amino acids like glutamic acid. It has a calculated pi of 4.19 and a molecular mass of 34.272 kDa. In hybrid selection/in vitro translation and in vitro transcription/translation experiments a translational product of 54 kDa was synthesized. The difference betw een apparent and calculated molecular mass is thought to be due to the relatively high amount of glutamic acid residues clustered in two reg ions. The developmental profile of expression of the corresponding gen e was analyzed by northern blot hybridization using a cDNA probe. The time course of expression is coincident with developmentally regulated metamorphic changes in the integument.