Cytodiffrentiation in the accessory glands of Tenebrio molitor. VI. A congruent map of cells and their secretions in the layered elastic product of the male bean‐shaped gland

Abstract

The morphology of the bean-shaped accessory glands (BAGs) of males of Tenebrio molitor is described. All cells in the secretory epithelium are long and narrow (300-400 mμ × 5 mμ). The seven types of secretory cells are distinguished from one another by the morphology of their secretory granules. Granule substructure varies from simple spheres with homogeneous electrondense contents to complex forms with thickened exterior walls or with crystalline and membranous contents. Individual cell types were mapped by staining whole glands with Oil Red O, and the cell distributions were confirmed by wax histology and ultramicroscopy. The secretions of all seven cell types form a secretory plug composed of seven layers. During mating, the secretory plug from each BAG is forced into the ejaculatory duct by contractions of a sheath of circular muscle. The mirror image plugs from symmetrical BAGs fuse and are transformed into the wall of the spermatophore.

Ultrastructural Localization of Basic Proteins and Carbohydrates in Male Accessory Glands of Two Triatoma Species (Hemiptera, Reduviidae, Triatominae)

“…The secretions produced by the male accessory glands of insects are constituted by heterogeneous substances (Odhiambo 1969, Gerber et al 1971, Dailey et al 1980; this is corroborated by the results obtained in this study that showed granules with positive reactions for carbohydrates and proteins simultaneously.…”

Structure of the male reproductive accessory glands ofPterostichus nigrita(Coleoptera: Carabidae), their role in spermatophore formation

“…In Orthoptera, the spermatophore is formed by secretions from different accessory gland tubules (Kaulenas 1992;Marchini et al 2009), each tubule producing different proteins. In T. molitor, the spermatophore is produced by a pair of bean-shaped accessory glands, each gland possessing seven types of epithelial cell organized as homogeneous populations (Dailey et al 1980). Each cell type produces a specific product that contributes to a layered secretory plug which contains spermatophorins used in the construction of the spermatophore (Happ 1992).…”

“…Surprisingly, little is known about the secretions and tissue structure of the accessory glands of Coleoptera, especially at a fine structural level. To date, information is available from four species only, Leptinotarsa decemlineata (Chrysomelidae) (De Loof and Lagasse 1972), Tenebrio molitor (Tenebrionidae) (Gadzama et al 1977;Dailey et al 1980;Grimes and Happ 1980;, Acanthoscelides obtectus (Bruchidae) (Huignard 1975;Cassier and Huignard 1979), and Bruchidius atrolineatus (Glitho and Huignard 1990).…”

“…Well-developed Golgi bodies are also a common feature of biosynthetically active gland cells of male insects (e.g. Bairati 1968;Odhiambo 1969a;Gadzama et al 1977;Riemann and Thorson 1979;Dailey et al 1980;Glitho and Huignard 1990;Kaulenas 1992;Dallai et al 1997;Fernandez and Cruz-Landim 2005;Marchini and Del Bene 2006;Marchini et al 2009;Radhakrishnan et al 2009). However, in the gland cells of some species of male insect, the Golgi bodies are scarce and poorly developed (Dapples et al 1974;Cassier and Huignard 1979) which is also the case in P. nigrita.…”

Ordered flow of secretion from accessory glands to specific layers of the spermatophore of mealworm beetles: Demonstration with a monoclonal antibody

“…The granules of cell type 5 are granular while those of cell type 7 contain membranous whorls (Dailey et al, 1980). With the gentler fixation schedule used for immunocytochemistry, inorphological preservation was not optimal (e.g., Fig.…”