Glycoconjugate profiles of insect spermatogenesis: Lectin cytochemical analysis of the cricket, Gryllus bimaculatus

The distribution of glycoconjugate in testicular germ cells of the cricket, Gryllus bimaculatus, was cytochemically investigated using a panel of lectins and several kinds of glycosidases. Observations were focused on the early process of spermatogenesis. The binding pattern with N-acetylgalactosamine-binding lectins, especially with Dolichos biflorus agglutinin, and their susceptibility to peptide-N-glycosidase F (PNGase F) suggested the stage-specific expression of N-linked glycoproteins with terminal α-N-acetylgalactosamine in the early meiotic prophase. In the primary spermatocyte, the transitory expression of PNGase F-resistant glycoproteins was detected by several mannose-binding and fucose-binding lectins such as Lens culinaris agglutinin and Anguilla anguilla agglutinin. Hyaluronidase-sensitive glycoconjugates also distributed widely in cricket testes, exemplified by perinuclear granular structures recognized by Helix pomatia agglutinin and nuclear staining with Phaseolus lunatus agglutinin. These lectin-binding affinities in meiotic prophase were discussed in reference to many informations about carbohydrate-lectin binding specificities.