Structural and functional diversification of follicular epithelium in Coreus marginatus (Coreidae: Heteroptera)

Follicular cells in Coreus marginatus are diversified into two main subpopulations of different cell morphology, ultrastructure, distribution of F-actin and ionic communication between oocyte and follicular cells. Cells forming the insert between the operculum and the bottom of the egg envelope and, subsequently, a circle of micropylar processes were retarded as compared to the developmental advancement of follicular cells in the equatorial part of ovarian follicle. Pinocytotic and vitellogenic activity in the ooplasm adjoining the insert cells were lower than in other regions. The inhibition of vitellogenesis in the neighbourhood of insert cells, which were not in ionic contact with the ooplasm, supports the hypothesis that there is a relation between follicular cell development and the regional intensity of vitellogenesis in heteropteran ovarian follicles.