Browsing by Subject "Fertilization"
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- PublicationOpen AccessGenes Encoding Mammalian Oviductal Proteins Involved in Fertilization are Subjected to Gene Death and Positive Selection(2018) Fouchécourt, Sophie; Goudet, Ghylène; Monget, Philippe; Moros Nicolás, Carla; Biología Celular e HistologíaOviductal proteins play an important role in mammalian fertilization, as proteins from seminal fluid. However, in contrast with the latter, their phylogenetic evolution has been poorly studied. Our objective was to study in 16 mammals the evolution of 16 genes that encode oviductal proteins involved in at least one of the following steps: (1) sperm–oviduct interaction, (2) acrosome reaction, and/or (3) sperm–zona pellucida interaction. Most genes were present in all studied mammals. However, some genes were lost along the evolution of mammals and found as pseudogenes: annexin A5 (ANXA5) and deleted in malignant brain tumor 1 (DMBT1) in tarsier; oviductin (OVGP1) in megabat; and probably progestagen-associated endometrial protein (PAEP) in tarsier, mouse, rat, rabbit, dolphin, and megabat; prostaglandin D2 synthase (PTGDS) in microbat; and plasminogen (PLG) in megabat. Four genes [ANXA1, ANXA4, ANXA5, and heat shock 70 kDa protein 5 (HSPA5)] showed branch-site positive selection, whereas for seven genes [ANXA2, lactotransferrin (LTF), OVGP1, PLG, S100 calcium-binding protein A11 (S100A11), Sperm adhesion molecule 1 (SPAM1), and osteopontin (SPP1)] branch-site model and model-site positive selection were observed. These results strongly suggest that genes encoding oviductal proteins that are known to be important for gamete fertilization are subjected to positive selection during evolution, as numerous genes encoding proteins from mammalian seminal fluid. This suggests that such a rapid evolution may have as a consequence that two isolated populations become separate species more rapidly
- PublicationOpen AccessLipid peroxidation was associated to the impairment of the fertilizing capability of gilthead sperm exposed to surfactants(Murcia : F. Hernández, 2007) Rosety, M.A.; Rosety, I.; Frias, L.; Rosety, J.M.; Ordóñez Muñoz, F.J.; Rosety-Rodriguez, M.The present study was designed to determine whether lipid peroxidation was associated with the impairment of the fertilizing capability of gilthead sperm after acute exposure to anionic surfactant Sodium Dodecyl Sulphate (SDS). Spawned eggs and sperm were collected from adult giltheads. Sperm suspensions (108 spermatozoa/mL) were dosed separately with different concentrations of SDS (0.6, 1.5, 3 and 6 mg/L) for 60 minutes. After this period, sperm samples were randomly distributed for both outcome measurements: fertilization percentage or lipid peroxidation assessment. On one hand, exposed sperm and unexposed eggs were combined for 20 minutes during which fertilization took place. Fertilization, defined as the presence of a fertilization envelope, was assessed by microscopic observation. On the other hand lipid peroxidation on exposed gilthead sperm was determined by estimating the production of malondialdehyde (MDA). Acute exposure to SDS caused a significant inhibitory effect on fertilization success in gilthead. It also increased significantly lipid peroxidation in exposed sperm. Furthermore, a strong but negative statistical association was found between fertilizing capability and lipid peroxidation gilthead sperm exposed to SDS. Although extrapolation from the laboratory to the field requires caution, the results of this work demonstrated that the impairment of fertilization was significantly associated with lipid peroxidation induced by acute exposure to SDS. Consequently lipid peroxidation may be recommended as an early-warning bioindicator of exposure to surfactants. Further studies are required.
- PublicationOpen AccessMitosis in the human embryo, the vital role of the sperm centrosome (centriole)(Murcia : F. Hernández, 1997) Sathananthan, A.H.The pattern of sperm centrosomal (centriolar) inheritance, centrosomal replication and perpetuation during mitosis of the human embryo is reviewed with a series of electron micrographs. Embryonic cleavage involves repeated mitoses, a convenient sequence to study centriolar behaviour during cell division. After the paternal inheritance of centrioles in the human was reported (Sathananthan et a1.,1991a), there has been an upsurge of centrosomal research in mammals, which largely follow the human pattern. The human egg has an inactive non-functional centrosome. The paternal centrosome contains a prominent centriole (proximal) associated with pericentriolar material which is transmitted to the embryo at fertilization and persists during sperm incorporation. Centriolar duplication occurs at the pronuclear stage (interphase) and the centrosome initially organizes a sperm aster when male and female pronuclei breakdown (prometaphase). The astral centrosome containing diplosomes (two typical centrioles) splits and relocates at opposite poles of a bipolar spindle to establish bipolarization, a prerequisite to normal cell division. Single or double centrioles occupy pivotal positions on spindle poles and paternal and maternal chromosomes organize on the equator of a metaphase spindle, at syngamy. Bipolarization occurs in al1 monospermic and in most dispermic ova. Dispermic embryos occasionally form two sperm asters initially and produce tripolar spindles (tripolarization). Anaphase and telophase follows producing two or three cells respectively, completing the first cell cycle. Descendants of the sperm centriole were found at every stage of preimplantation embryo development and were traced from fertilization through cleavage (first four cell cycles) to the morula and hatching blastocyst stage. Centrioles were associated with nuclei at interphase, when they were often replicating and occupied pivotal positions on spindle poles during mitosis. Sperm remnants were associated with centrioles Offprint requests to: Dr. A.H. Sathananthan, Associate Professorl Reader, Faculty of Health Sciences. La Trobe University, Bundoora, Victoria 3083, Australia and were found at most stages of cleavage. Centrioles were found in trophoblast, embryoblast and endoderm cells in hatching blastocysts. Pericentriolar, centrosomal material nucleated astral and spindle microtubules. Abnormal nuclear configurations observed in embryos reflect mitotic aberrations. The bovine embryo closely resembles the human embryo in centriolar behaviour during mitosis. It is concluded that the sperm centrosome is the functional active centrosome in humans and is likely the ancestor of centrioles within centrosomes in foetal and adult somatic cells. The role of the sperm centrosome in embryogenesis and male infertility is discussed, since it is of clinical importance in assisted reproduction.
- PublicationRestrictedOocytes use the plasminogen-plasmin system to remove supernumerary spermatozoa(2012-05-03) Grullón LA; Coy Fuster, Pilar; Jíménez Movilla, María; García Vázquez, Francisco Alberto; Mondéjar Corbalán, Irene; Romar Andrés, Raquel; Romar Andrés, Raquel; Fisiologíabackground: The role of the plasminogen-plasmin (PLG-PLA) system in fertilization is unknown, although its dysfunction has been associated with subfertility in humans. We have recently detected and quantified plasminogen in the oviductal fluid of two mammals and showed a reduction in sperm penetration during IVF when plasminogen is present. The objective of this study was to describe the mechanism by which PLG-PLA system regulates sperm entry into the oocyte. methods and results: By combining biochemical, functional, electron microscopic, immunocytochemical and live cell imaging methods, we show here that (i) plasminogen is activated into the protease plasmin, by gamete interaction; (ii) urokinase-type and tissuetype plasminogen activators are present in oocytes, but they are not of cortical granule origin; (iii) sperm binding to oocytes triggers the releasing of plasminogen activators and (iv) the generated plasmin causes sperm detachment from the zona pellucida. conclusions: Our results describe a novel mechanism for the success or failure of fertilization in mammals, by which molecules present in the oviductal environment are activated by molecules originating within the gametes. We anticipate that therapeutic up- or down-regulation of this physiological mechanism may be used to help in conception or as a contraceptive tool. Since components of the PLG-PLA system are already available as drugs for heart attacks or cancer therapies, basic research on this novel function would be rapidly transferable for clinical application.
- PublicationOpen AccessOvarian development in mice bearing homozygous or heterozygous null mutations in zona pellucida glycoprotein gene mZP3(Murcia : F. Hernández, 1998) Wassarman, P.M.; Liu, C.; Chen, J.; Qi, H.; Litscher, E.S.The plasma membrane of all mammalian eggs is surrounded by a thick extracellular coat, the zonu pellirc.id(i (ZP), whose paramount function is to regulate species-specific fertilization. The mouse egg ZP is composed of only three glycoproteins, mZPI -3, that are synthesized and secreted exclusively by oocytes during their 2-3 week growth phase. Disruption of the rnZP3 gene by targeted mutagenesis in embryonic stem (ES) cells yields mice heterozygous ( r n ~ P 3 + / -o)r hornozygous ( r n ~ P 3 - / -f)o r the null mutation. As expected, male mice bearing the null mutation are indistinguishable from wild-type males with respect to viability and fertility. Female m ~ ~ 3 +m/ic-e are as fertile as wild-type animals, but their eggs have a thin ZP (-2.7 pm thick) as compared to the ZP (-6.2 pm thick) of eggs from wild-type animals. On the other hand, female rn~P3-/m- ice are infertile and their eggs lack a ZP. The infertility apparently is due to the lack of a sufficient number of eggs in oviducts of superovulated ~ZPJ-lfemales. Light micrographs reveal that development of ovarian follicles is often retarded in rnz~3- l -m ice as compared to wild-type animals. This is manifested as reduced ovarian weights, reduced numbers of Graafian follicles, and reduced numbers of fully-grown oocytes in I ~ Z P ~ -f/em- ales. I t seems likely that the pleiotropic effects of the homozygous null mutation on ovarian development may be due, at least in part, to disruption of intercellular communication between growing oocytes and their surrounding follicle cells.
- PublicationOpen AccessPhysiological functions of seminal vesicle secretions in male fertility(2026) Taichi Noda1; Ayumu Taira1; Biología Celular e Histología; Universidad de Murcia, Departamento de Biologia Celular e HistiologiaIn many mammals, accessory gland secretions are ejaculated into the female reproductive tract, along with sperm, and the prostates and seminal vesicles are the main glands responsible for these secretions. Cauda epididymal sperm can efficiently fertilize eggs in vitro; however, we found that seminal vesicle secretions improved sperm fertilization rates in vivo by artificial insemination. Furthermore, using the seminal vesicle-removed mice, other studies have shown that seminal vesicle secretions contribute to embryogenesis and offspring health by regulating the environment in the female reproductive tract. These results indicate the significance of accessory gland secretions in fertilization and development in vivo. More than 700 proteins are present in the accessory glands, and genome editing accelerates the functional analysis of these proteins at the individual level. For example, some studies reported results from phenotypic analyses of genetically modified mice that were different from those of in vitro experiments. In this review, we discuss the current findings on the effects of accessory gland secretions on male fertility and the future prospects. Histol Histopathol
- PublicationOpen AccessRabbit zona pellucida composition: A molecular, proteomic and phylogenetic approach(2012) Stetson, I.; Chevret, P.; Lorenzo, P.L.; Ballesta, J.; Rebollar, P.G.; Gutiérrez-Gallego, R.; Izquierdo Rico, María José; Avilés Sánchez, Manuel; Moros Nicolás, Carla; Biología Celular e HistologíaThe zona pellucida (ZP) participates in sperm–egg interactions during the first steps of 22 fertilization. Recent studies have shown that the ZP matrix of oocytes in several species is 23 composed of four glycoproteins, designated as ZP1, ZP2, ZP3 and ZP4, rather than the three 24 described in mouse, pig and cow. In this study, investigations were carried out to unveil a Q425 fourth glycoprotein in the rabbit (Oryctolagus cuniculus) ZP. Using total RNA isolated from 26 rabbit ovaries, the complementary deoxyribonucleic acid (cDNA) encoding rabbit ZP1 was 27 amplified by reverse transcribed polymerase chain reaction (RT-PCR). The ZP1 cDNA 28 contains an open reading frame of 1825 nucleotides encoding a polypeptide of 608 amino 29 acid residues. The deduced amino acid sequence of rabbit ZP1 showed high identity with 30 other species: 70% identity with human and horse ZP1, and 67% identity with mouse and rat 31 ZP1. At the proteomic level, peptides corresponding to the four proteins were detected by 32 mass spectrometry. In addition, a molecular phylogenetic analysis of ZP1 showed that 33 pseudogenization of this gene has occurred at least four times during the evolution of 34 mammals. The data presented in this manuscript provide evidence, for the first time, that 35 the rabbit ZP is composed of four glycoproteins.