Identification, description, and activity of proteins in the tergal glands of the German cockroach, Blattella germanica (L.)

Myers, Aaron J. M.S., Purdue University, May 2015. Identification, description, and activity of proteins in the tergal glands of the German cockroach, Blattella germanica (L.). Major Professors: Gary Bennett and Mike Scharf. German cockroaches are important urban pests that have been linked to asthma and serious allergic reactions in sensitized individuals. In this research project I, (i) identified different proteins expressed in the tergal glands of male German cockroaches, (ii) determined the expression levels of these proteins in different cockroach life stages and tissues, and (iii) investigated the role of the tergal gland alpha-amylase (BGTG-1) protein. Four major tergal gland proteins were separated on denaturing polyacrylamide gels. With peptide sequencing two of these proteins were identified as alpha-amylase (BGTG-1) and Blattella germanica allergen 2 (Bla g 2). Both of these proteins showed highest relative expression in adult male tergal glands as compared to other body parts of adult males, non-gravid females and gravid females. Enzyme assays and RNA interference (RNAi) based silencing of the BGTG-1 gene/protein, provided preliminary evidence that it hydrolyzes starch to release maltose. Overall, proteins found in the tergal glands of male German cockroaches appear to be serving potentially important roles within the glands. Future research will identify the functional roles of these proteins in cockroach mating behavior and allergen biology.