The sperm structure and spermiogenesis of the heteropteran Coptosoma scutellatum (Geoffroy) with emphasis on the development of the centriole adjunct

Autor: David Mercati, Glenda Dias, Romano Dallai, José Lino-Neto
Rok vydání: 2016
Předmět:
Zdroj: Micron. 82:33-40
ISSN: 0968-4328
DOI: 10.1016/j.micron.2015.12.005
Popis: The sperm structure and spermiogenesis of the morphologically peculiar heteropteran Coptosoma scutellatum has been examined with electron microscopy. The sperm has a short monolayer acrosome, a cylindrical nucleus, a 9+9+2 axoneme and two mitochondrial derivatives with crystallized matrix. It shows the synapomorphies typical of the group, consisting of (a) two crystallized areas in the mitochondrial derivatives; (b) the presence of two bridges connecting the intertubular material of the flagellar axoneme to the flattened cisterns adhering to the inner sides of the mitochondrial derivatives; (c) the absence of accessory bodies. The most interesting feature is the presence, in the early spermatid, of an extended centriole adjunct material with the shape of a large ribbon-like structure. This material surrounds the posterior nuclear region and extends anteriorly along the nucleus. It is a microtubule-organizing-center (MTOC) producing the many microtubules surrounding the sperm components At the end of spermiogenesis, the centriole adjunct material modifies into two kidney-like structures accompanying the nuclear posterior end and surrounding the modified centriole.
Databáze: OpenAIRE