ABSTRACT
Diapause is a genetically controlled life phase in which the biochemical and behavioral adjustaments that occur in advance are followed by a refractory period of suppressed development. In this study, we investigated whether spermiogenesis in phytophagous bugs continues in adult diapause. The morphology of spermiogenesis during this phase was examined. During diapause, the testes of phytophagous insects contained vesicles similar to residual bodies. These vesicles showed acid phosphatase activity, which suggested that they were active lysosomes. In addition, the nucleus of spermatids showed an apoptotic pattern with fragmented chromatin. These results indicate that spermiogenesis is discontinued during adult diapause in these bugs, and that apoptotic and phagocytic events may be involved.
Subject(s)
Animals , Heteroptera/anatomy & histology , SpermatozoaABSTRACT
The ultrastructural detection of calcium using pyroantimonate, and the immunocytochemical localization of calmodulin using monoclonal antibody were carried out during the spermiogenesis of phytophagous bugs. The presence of calcium was observed on the Golgi apparatus during the initial phases of spermiogenesis. In the other stages the calcium was observed in association with the nucleus and in some regions of acrosome. Indeed, it was detected surrounding the mitochondrial derivatives and specific axonemal microtubules on the tail region. The immunocytochemical detection of calmodulin showed the presence of this protein approximately in the same regions where the calcium was detected, indicating that calcium and calmodulin could work together during spermiogenesis of this phytophagous bugs, suggesting their involvement on the regulation of flagellar beating, nuclear compactation and acrosome formation.