Within the testicular cysts of the mussel Prisodon alatus are numerous somatic host cells described as Sertoli cells (SC), each containing a variable number of young spermatid morulae. Among them, several free spermatid morulae, spermatids, and spermatozoa were observed. Each free spermatid morula is surrounded by an external membrane. The early spermatids enclosed within the morulae have dense and homogeneous chromatin, and the cytoplasm occupies little space around the nucleus. Later, during spermiogenesis, the SC show lysis and disrupt to liberate the spermatid morulae. The membrane of the free morula is then disrupted, releasing the young spermatids. The SC disappear just after the appearance in the testis of a large number of free young spermatids. The nucleus of each free spermatid becomes gradually smaller and denser by the appearance of a granular pattern of condensed chromatin. During the maturation phase of the spermatids, the cytoplasm becomes more voluminous, and mitochondria and centrioles are more evident. Then, flagellogenesis occurs, and the nucleus gradually condenses into thicker strands. In the mature sperm, the apical zone has a disc-shaped acrosomal vesicle and the midpiece contains five mitochondria and two centrioles located at the same level. The flagellum has the common 9+2 microtubular pattern. The results are discussed with particular reference to Sertoli cells and clusters of spermatid morulae with those of species of closely related taxa in the bivalves. J. Morphol. 238:63-70, 1998. © 1998 Wiley-Liss, Inc.
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http://dx.doi.org/10.1002/(SICI)1097-4687(199810)238:1<63::AID-JMOR5>3.0.CO;2-O | DOI Listing |
Biol Reprod
December 2022
Laboratory of Mammalian Molecular Embryology, College of Animal Sciences, Zhejiang University, Hangzhou, Zhejiang, China.
Linker histone H1 binds to the nucleosome and is implicated in the regulation of the chromatin structure and function. The H1 variant H1FOO is heavily expressed in oocytes and early embryos. However, given the poor homology of H1FOO among mammals, the functional role of H1FOO during preimplantation embryonic development remains largely unknown, especially in domestic animals.
View Article and Find Full Text PDFDevelopment
August 2022
Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany.
Profilin 4 (Pfn4) is expressed during spermiogenesis and localizes to the acrosome-acroplaxome-manchette complex. Here, we generated PFN4-deficient mice, with sperm displaying severe impairment in manchette formation. Interestingly, HOOK1 staining suggests that the perinuclear ring is established; however, ARL3 staining is disrupted, suggesting that lack of PFN4 does not interfere with the formation of the perinuclear ring and initial localization of HOOK1, but impedes microtubular organization of the manchette.
View Article and Find Full Text PDFJ Exp Zool B Mol Dev Evol
March 2020
Hubei Key Laboratory of Genetic Regulation and Integrative Biology, School of Life Sciences, Central China Normal University, Wuhan, P. R. China.
Arginine methylation is an important posttranslational modification and catalyzed by a family of protein arginine methyltransferases (PRMTs). PRMT7 is the type III PRMT and produces solely monomethylarginine products. PRMT7 has been found to play important roles in multiple biological processes in mammals.
View Article and Find Full Text PDFJ Reprod Dev
June 2019
Department of Advanced Pathobiology, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan.
Piezo-actuated intracytoplasmic sperm injection (Piezo-ICSI) is used as an efficient in vitro fertilization method with various animals. With this method, elongated spermatids are collected from testicular tissues and are easier to obtain from animals that unexpectedly die than ejaculate sperm. Additionally, elongated spermatid injection often results in the development of embryos and offspring.
View Article and Find Full Text PDFZhonghua Nan Ke Xue
December 2017
Center of Reproductive Medicine, The 105th Hospital of PLA, Hefei, Anhui 230031, China.
Objective: To investigate the application value of the frozen-thawed round spermatids of the mouse in in vitro fertilization (IVF).
Methods: Haploid spermatids of the mouse obtained in vitro were divided into a frozen-thawed and a fresh group and oocytes were collected from 6-8 weeks old female mice. After diamidino-phenyl-indole (DAPI) staining, the oocytes were subjected to intracytoplasmic round spermatid injection (ROSI), 259 in the frozen-thawed and 238 in the fresh group.
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