TYROSINASE-TYPE PROPHENOLOXIDASE DISTRIBUTION IN THE ALIMENTARY CANAL OF STRAINS OF ANOPHELES-GAMBIAE REFRACTORY AND SUSCEPTIBLE TO PLASMODIUM INFECTION

Tyrosinase-type prophenoloxidase distribution was investigated in the posterior midgut and salivary glands of strains of noninfected adult Anopheles gambiae refractory (Blue strain) and susceptible (G3 strain) to infection with malaria parasites. Immunocytochemical localization showed that in the posterior midgut epithelium tyrosinase-type prophenoloxidase was almost entirely restricted to apical granules. These are known to be a mixture of secretory grannies and lysosomes; it was not possible to distinguish between the two in this study. The secretory product in the lumen of the distal median lobe of the salivary gland was heavily labeled; the secretory product in the lumen of the distal lateral lobes was also labeled but to a lesser extent. Subjectively, no differences in the degree or pattern of labeling of either midgut or salivary glands between the strains of mosquito were apparent. (C) 1995 Academic Press, Inc.