title: Spermatogenesis in the blue swimming crab, Portunus pelagicus, and evidence for histones in mature sperm nuclei.
abstract: Spermatogenesis in the blue swimming crab, Portunus pelagicus, is described by light and electron microscopy. The testis is composed of anterior (AT) and posterior (PT) lobes, that are partitioned into lobules by connective tissue trabecula, and further divided into zones (germinal, transformation and evacuation), each with various stages of cellular differentiation. The vas deferens is classified into three distinct regions: anterior (AVD), median (MVD), and posterior (PVD), on the presence of spermatophores and two secretions, termed substance I and II. Based on the degree and patterns of heterochromatin, spermatogenesis is classified into 13 stages: two spermatogonia (SgA and SgB), six primary spermatocytes (leptotene, zygotene, pachytene, diplotene, diakinesis, and metaphase), a secondary spermatocyte (SSc), three spermatids (St 1-3), and a mature spermatozoon. Spermatid stages are differentiated by chromatin decondensation and the formation of an acrosomal complex, which is unique to brachyurans. Mature spermatozoa are aflagellated, and have a nuclear projection and a spherical acrosome. AUT-PAGE and Western blots show that, during chromatin decondensation, there is a reduction of most histones, with only small amounts of H2B and H3 remaining in mature spermatozoa.
authors.affiliation: School of Medicine, Deakin University, Geelong, Victoria 3217, Australia. mjstewa@deakin.edu.au
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stewart
authors.forename: Praphaporn
authors.initials: P
authors.lastname: Stewart
authors.forename: Nantawan
authors.initials: N
authors.lastname: Soonklang
authors.forename: Vichai
authors.initials: V
authors.lastname: Linthong
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hanna
authors.forename: Wei
authors.initials: W
authors.lastname: Duan
authors.forename: Prasert
authors.initials: P
authors.lastname: Sobhon
mesh_terms: D000177:Acrosome / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D003386:Brachyura / Q000166:cytology* / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism* / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D019084:Fluorescent Antibody Technique, Indirect; D006657:Histones / Q000378:metabolism*; D008297:Male; D013079:Sperm Maturation / Q000502:physiology*; D013094:Spermatozoa / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D013550:Swimming / Q000502:physiology*; D014649:Vas Deferens / Q000166:cytology / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D006657:Histones