Comparison between cuticular proteins from two locust species, Locusta migratoria and Schistocerca gregaria

Abstract

Proteins from various cuticular regions of pharate adults of the desert locust ( Schistocerca gregaria) were compared to the proteins in corresponding cuticular samples from pharate adults of the migratory locust ( Locusta migratoria) by means of two-dimensional electrophoresis. Endocuticular proteins from abdominal cuticle from mature adults of both species were similarly compared, and their relative abundance was determined. Pronounced similarities in protein patterns were observed between the two species, and regional differences corresponding to those formerly described in L. migratoria were also found in S. gregaria. The endocuticular samples from the two species are similar with respect to titration curves and amino acid composition of individual proteins. Sex-related differences in endocuticular protein pattern are found in both species. An albino strain of S. gregaria shows the same protein pattern as the wild-type for both pharate and mature imaginal cuticular samples. The similarities in protein composition in the cuticle of the two locust species are so pronounced, that it can be proposed that all the main features in the structures of the proteins have been conserved, and that these features may be important in determining the specific folding of the protein molecules and their mutual interactions, thereby optimizing the properties of the cuticle.