Sperm-cell ultrastructure of North American sturgeons. I. The Atlantic sturgeon (Acipenser oxyrhynchus)

1998 ◽  
Vol 76 (10) ◽  
pp. 1822-1836 ◽  
Author(s):  
Martin N DiLauro ◽  
Wayne Kaboord ◽  
Rosemary A Walsh ◽  
William F Krise ◽  
Michael A Hendrix
Keyword(s):  
Electron Microscopy ◽  
Sperm Cell ◽  
Evolutionary Relationship ◽  
Lake Sturgeon ◽  
White Sturgeon ◽  
Evolutionary Relationships ◽  
Head Width ◽  
Sperm Cells ◽  
Atlantic Sturgeon ◽  
Stellate Sturgeon

Atlantic sturgeon (Acipenser oxyrhynchus) and lake sturgeon (Acipenser fulvescens) sperm-cell morphologies were examined using scanning electron microscopy. Major differences were found in four of nine metrics, all in the head region of the cell. Atlantic sturgeon sperm cells were much shorter than those of lake sturgeon. Anterior head width exceeded posterior head width, in contrast to the arrangement in lake sturgeon sperm cells. Lake sturgeon sperm cells are nearer in size to those of other sturgeons than are Atlantic sturgeon sperm cells. Comparisons were made with sperm-cell structures known from other sturgeon species, including the Russian sturgeon (Acipenser gueldenstaedti colchicus), stellate sturgeon (Acipenser stellatus), Chinese sturgeon (Acipenser sinensis), and white sturgeon (Acipenser transmontanus). Variation in cell morphology may indicate evolutionary relationships. In addition, the fine structure of Atlantic sturgeon sperm cells was examined using transmission electron microscopy and selected metrics are described. The cell possesses a distinct acrosome, a midpiece, and a single flagellum. A comparison is made with ultrastructural details of the sperm cells of stellate and white sturgeons. Similarities among these species include radial symmetry about the longitudinal axis, an elongate shape, a distinct acrosome, and the presence of endonuclear canals. Noteworthy differences include a smaller total length and width than stellate and white sturgeon sperm cells. The main sperm-cell body is approximately 4 µm long and the flagellum about 37 µm long, resulting in a total cell length of about 41 µm. Also, the Atlantic sturgeon sperm cell possesses only two membraned endonuclear canals, in contrast to the arrangement in white and stellate sturgeons, where three such organelles are found. A structural connection of unknown function between the nuclear fossa and proximal centriole is also present in the Atlantic sturgeon sperm cell. Sperm-cell nuclei of white and stellate sturgeons are elongate trapezoids, with the anterior end narrower, whereas in Atlantic sturgeon the anterior portion of the trapezoid is wider than the posterior. Structural similarities between species may indicate a commonality of ancestral and evolutionary relationships that may have taxonomic implications. Ultrastructure suggests a closer evolutionary relationship between the white and stellate sturgeon than between either of these species and the Atlantic sturgeon. The present findings may be used by biologists studying the reproductive physiology, forensics, taxonomy, and genetics of sturgeons.

Sperm-cell ultrastructure of North American sturgeons. III. The lake sturgeon (Acipenser fulvescens Rafinesque, 1817)

2000 ◽  
Vol 78 (3) ◽  
pp. 438-447 ◽  
Author(s):  
Martin N DiLauro ◽  
Wayne S Kaboord ◽  
Rosemary A Walsh
Keyword(s):  
Sperm Cell ◽  
Radial Symmetry ◽  
Lake Sturgeon ◽  
Acipenser Fulvescens ◽  
Sperm Cells ◽  
Shortnose Sturgeon ◽  
Atlantic Sturgeon ◽  
Cell Nuclei ◽  
Head Region ◽  
Anterior Portion

Lake sturgeon (Acipenser fulvescens) sperm cell fine structure was examined using transmission electron microscopy. The cell possesses a distinct acrosome, a defined head region, a midpiece, and a single flagellum. Sperm cells of this species share a general radial symmetry, an elongate shape, a distinct acrosome, and the presence of endonuclear canals with those of other sturgeons. The mean length of the lake sturgeon sperm cell body (acrosome + nucleus + midpiece) is approximately 7.13 µm and the length of the flagellum is about 50 µm, resulting in a total cell length of about 57 µm. The lake sturgeon sperm cell is much longer and slightly wider than that of the Atlantic sturgeon. The sperm-cell nuclei of lake, shortnose, white, and stellate sturgeons are elongate trapezoids in shape, with the anterior (acrosome) end narrowest but, in the Atlantic sturgeon, the anterior portion of the trapezoid is wider than the posterior. Although slightly smaller in total length and width, the lake sturgeon sperm cell is most similar to the shortnose sperm cell in ultrastructure, overall size, and shape; it also shares similarity of shape with the stellate and white sturgeon sperm cells. The cell nuclei of these four sturgeons have three endonuclear canals. The acrosome of the lake sturgeon sperm cell has longer posterolateral projections than that of the Atlantic or shortnose sturgeon sperm cell. A structural connection, the fibrous body, is present in the lake sturgeon sperm cell between the nuclear fossa and the proximal centriole, as in the Atlantic and shortnose sturgeon sperm cells. Our results suggest a more recent evolutionary linkage between the lake and shortnose sturgeons than with the Atlantic sturgeon. This work presents the first ultrastructural description of the lake sturgeon sperm cell.

Sperm-cell ultrastructure of North American sturgeons. II. The shortnose sturgeon (Acipenser brevirostrum, Lesueur, 1818)

1999 ◽  
Vol 77 (2) ◽  
pp. 321-330 ◽  
Author(s):  
Martin N DiLauro ◽  
Wayne S Kaboord ◽  
Rosemary A Walsh
Keyword(s):  
Sperm Cell ◽  
Cell Ultrastructure ◽  
Sperm Cells ◽  
Shortnose Sturgeon ◽  
Atlantic Sturgeon ◽  
Head Region ◽  
Acipenser Brevirostrum ◽  
Transmission Electron ◽  
Structural Connection ◽  
Single Flagellum

The fine structure of the sperm cell of the shortnose sturgeon (Acipenser brevirostrum) was examined using transmission electron microscopy and selected metrics. The cell possesses a distinct acrosome, a defined head region, a midpiece, and a single flagellum. The mean length of the sperm cell body (acrosome + nucleus + midpiece) is approximately 9.71 µm, and the length of the flagellum is about 37 µm, resulting in a total cell length of about 46 µm. The sperm cell of the shortnose sturgeon is much longer and slightly wider than that of the Atlantic sturgeon. The nuclei of shortnose, white, and stellate sturgeon sperm cells are elongate trapezoids with the anterior (acrosome) end narrowest, the opposite of that of the Atlantic sturgeon. Although slightly smaller in total length and width than the sperm cells of the stellate and white sturgeons, that of the shortnose sturgeon is most similar to them in overall ultrastructure, as all three cells have three endonuclear canals. A structural connection of unknown function between the nuclear fossa and the proximal centriole, which is similar to the fibrous body in other species, is present in the shortnose sturgeon sperm cell. Our results suggest a more recent evolutionary link between the shortnose, white, and stellate sturgeons than between any of these and the Atlantic sturgeon. This is the first description of sperm cell ultrastructure in the shortnose sturgeon, an endangered species.

Sperm-cell ultrastructure of North American sturgeons. IV. The pallid sturgeon (Scaphirhynchus albus Forbes and Richardson, 1905)

2001 ◽  
Vol 79 (5) ◽  
pp. 802-808 ◽  
Author(s):  
Martin N DiLauro ◽  
Rosemary A Walsh ◽  
Michelle Peiffer ◽  
Randy M Bennett
Keyword(s):  
Sperm Cell ◽  
Longitudinal Axis ◽  
Cell Ultrastructure ◽  
Sperm Cells ◽  
Atlantic Sturgeon ◽  
Ultrastructural Studies ◽  
Pallid Sturgeon ◽  
Oak Tree ◽  
Distal Centriole ◽  
Scaphirhynchus Albus

Sperm-cell morphology and ultrastructure in the pallid sturgeon (Scaphirhynchus albus) were examined using transmission and scanning electron microscopy. Metrics and structure were compared with similar metrics obtained from other published descriptions of sturgeon sperm cells. General morphology was found to be similar to that of sperm cells of the white (Acipenser transmontanus), lake (A. fulvescens), stellate (A. stellatus), Chinese (A. sinensis), Russian (A. gueldenstaedti colchicus), and shortnose (A. brevirostrum) sturgeons, which all shared a gradual tapering of the nuclear diameter from posterior to anterior, unlike that of the Atlantic sturgeon (A. oxyrhynchus). The sperm cell of the pallid sturgeon was similar in size to that of the Atlantic sturgeon, being only slightly larger. The sperm cell of the pallid sturgeon differed from those of other sturgeons chiefly in the acrosomal region, where the posterolateral projections (PLP) have the shape of an acute triangle and are arranged in a spiral about the longitudinal axis of the cell. The PLP were longer than those of other sturgeons, being twice the length of those of the Atlantic sturgeon and 58% longer than those of the lake sturgeon. Also, in cross section the acrosome had the shape of a hollow cone rather than the cap of an oak tree acorn, as was found in ultrastructural studies of other sturgeons. In addition, we were able to confirm that the structural arrangement of the distal centriole of the midpiece is identical with that of the proximal centriole: nine sets of microtubular triplets around the periphery of the centriole. This information is of potential use to fishery biologists, forensic biologists, zoologists, reproductive physiologists, taxonomists, evolutionary biologists, and aquaculturists.

scholarly journals Persistent directional growth capability in Arabidopsis thaliana pollen tubes after nuclear elimination from the apex

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kazuki Motomura ◽  
Hidenori Takeuchi ◽  
Michitaka Notaguchi ◽  
Haruna Tsuchi ◽  
Atsushi Takeda ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Pollen Tube ◽  
Sperm Cell ◽  
Pollen Tubes ◽  
Vegetative Nucleus ◽  
Sperm Cells ◽  
Apical Region ◽  
Basal Region ◽  
Specific Expression ◽  
Directional Growth

AbstractDuring the double fertilization process, pollen tubes deliver two sperm cells to an ovule containing the female gametes. In the pollen tube, the vegetative nucleus and sperm cells move together to the apical region where the vegetative nucleus is thought to play a crucial role in controlling the direction and growth of the pollen tube. Here, we report the generation of pollen tubes in Arabidopsis thaliana whose vegetative nucleus and sperm cells are isolated and sealed by callose plugs in the basal region due to apical transport defects induced by mutations in the WPP domain-interacting tail-anchored proteins (WITs) and sperm cell-specific expression of a dominant mutant of the CALLOSE SYNTHASE 3 protein. Through pollen-tube guidance assays, we show that the physiologically anuclear mutant pollen tubes maintain the ability to grow and enter ovules. Our findings provide insight into the sperm cell delivery mechanism and illustrate the independence of the tip-localized vegetative nucleus from directional growth control of the pollen tube.

scholarly journals Influence of Campylobacter fetus subsp. fetus on ram sperm cell quality

2008 ◽  
Vol 57 (11) ◽  
pp. 1405-1410 ◽  
Author(s):  
Tidhar Zan Bar ◽  
Ronen Yehuda ◽  
Tomer Hacham ◽  
Sigal Krupnik ◽  
Benjamin Bartoov
Keyword(s):  
Sperm Cell ◽  
Sperm Cells ◽  
Male Factor ◽  
Motility Index ◽  
Fas Receptor ◽  
Campylobacter Fetus ◽  
Fetus Subsp ◽  
Ram Sperm ◽  
Female Sheep

Campylobacter fetus subsp. fetus infection can occur in female sheep, causing infertility or abortion. Despite extensive research on the effect of these bacteria on female fertility, little research has been done on the influence of C. fetus subsp. fetus on the male factor. Our objective was to examine the influence of C. fetus subsp. fetus on ram sperm. Motility index, percentage of live spermatozoa, mean αt value (an indication of the chromatin stability of the sperm cell) and percentage of sperm cells expressing the FAS receptor were measured in sperm incubated in the presence or absence of C. fetus subsp. fetus. The motility index and viability of sperm incubated with the bacteria were lower than those of untreated sperm samples after 5 h. In bacteria-incubated sperm cells, the percentage expressing FAS receptor was already significantly elevated at 15 min. Bacteria-incubated sperm showed a greater prevalence of morphological damage. The bacteria were attached to tail and acrosome regions, and the sperm damage was concentrated in both the motility and chromatin regions. Bacteria-infected sperm cells showed a decrease in motility, increase in early acrosome reaction and chromatin damage. Similar effects were induced by incubation of the sperm with supernatants from C. fetus subsp. fetus cultures. Thus this study demonstrates that C. fetus subsp. fetus has a detrimental effect on the quality of ram sperm.

scholarly journals A Study of Aflatoxin on Sperm Cell Quality for Elderly People

2018 ◽  
Vol 6 (2) ◽  
pp. 45-49
Author(s):  
Akila CR ◽  
Dinesh Babu J ◽  
Sravan Kumar P ◽  
Vinaya B
Keyword(s):  
Elderly People ◽  
Sperm Cell ◽  
Sperm Cells

Mycotoxins represent poisonous materials produced via certain types of growths. Among different mycotoxins, aflatoxins are viewed as plainly hazardous, taking into account that they are portrayed as cancer-causing for creatures and individuals. The admission of aflatoxins by means of feeds or nourishments should cause pernicious results on creatures' or people's wellbeing. Exploration on creatures has indicated that the overall casing circumstance just as a portion of the blood boundaries, particularly those of the liver may be adversely influenced with aflatoxin the executives. As to conceptive device, in spite of the fact that not remarkably examined, a few specialists bolster the helpless impacts of aflatoxins both on women or on grown-up guys. More precisely, in male, the scale and weight of the genital organs, the spermatogenesis, the number, the motility and the morphology of sperm cells just as hormones' fixations can be influenced after presentation of the creatures to aflatoxins, making barrenness inconveniences additional normal. Most examination allude to lab and significantly less to viable creatures, while least complex two investigations look for counsel from the doable issues of barrenness on men in view of aflatoxins. Since imitation is made one out of the greatest fundamental areas of creature cultivation, exceptional intrigue should be paid to supplements with the goal that the chance of the aflatoxin admission by creatures could be evacuated, the creature wellbeing extraordinarily in regards to the conceptive gadget may be covered and financial misfortunes could be enhanced.

scholarly journals Expression and function of ras proto-oncogene proteins in human sperm cells

1992 ◽  
Vol 102 (3) ◽  
pp. 487-494 ◽  
Author(s):  
R.K. Naz ◽  
K. Ahmad ◽  
P. Kaplan
Keyword(s):  
Sperm Cell ◽  
Acrosome Reaction ◽  
Cell Function ◽  
Beat Frequency ◽  
Human Sperm ◽  
Sperm Cells ◽  
Ras Protein ◽  
Head Displacement ◽  
Sperm Penetration ◽  
And Function

The presence and role of c-ras proteins were investigated in mature human sperm cells. The v-H-ras monoclonal antibody (mAb) against the c-ras protein, p21, reacted specifically with the acrosomal region of methanol-fixed as well as unfixed-live capacitated and non-capacitated human sperm cell in the indirect immunofluorescence technique. The v-H-ras mAb predominantly recognized c-ras protein of 21 kDa on the Western blot of lithium diiodosalicylate (LIS)-solubilized human sperm preparation. The incubation of sperm cells with v-H-ras mAb affected the sperm cell function in the human sperm penetration assay. The antibody significantly reduced the acrosome reaction and release of acrosin activity from the sperm cells. There was no effect of the mAb on percentage motility, although the mAb significantly affected various motility characteristics such as linearity, amplitude of lateral head displacement (ALH) and beat frequency, the motility parameters involved in the hyperactivation phenomenon of sperm cells leading to capacitation and acrosome reaction. These results suggest that the c-ras or c-ras-like proteins are present in mature sperm cell and may have a role in capacitation and/or acrosome reaction of human sperm cell.

399 SPERMATOZOA-MEDIATED GENE TRANSFER IS INFLUENCED BY SIZE, STRUCTURE, AND CONCENTRATION OF EXOGENOUS DNA

2007 ◽  
Vol 19 (1) ◽  
pp. 315
Author(s):  
W. B. Feitosa ◽  
M. P. Milazzotto ◽  
E. A. L. Martins ◽  
A. M. Rocha ◽  
J. L. Avanzo ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Gel Electrophoresis ◽  
Sperm Cell ◽  
Reference Data ◽  
Size Structure ◽  
Specific Protein ◽  
Sperm Cells ◽  
Exogenous Dna ◽  
Mammalian Sperm ◽  
Cell Association

Mammalian sperm cells have a spontaneous ability to take up exogenous DNA in a process regulated by specific protein. However, little is known about the effect of exogenous DNA on sperm cell association. The aim of this work was to evaluate the effect of size, concentration, and structure of exogenous DNA sequence in apoptosis and oncosis induction and the association with spermatozoa. To evaluate the effect of size and concentration of exogenous DNA, sequences of 2.2, 5.5, and 8.5 kb were used at the concentrations of 500 ng (Experiment 1) or 5 × 1011 molecules (Experiment 2). To assess the effect of structure (Experiment 3), 3 sequences of approximately 500 bp were used, containing 65.7% of AT (AT sequence), 46.4% of AT (IN sequence), and 38.6% of AT (GC sequence). To evaluate apoptosis and oncosis in all treatments, sperm cells were incubated with exogenous DNA for 1 h, stained with 2 µL of Yo-Pro (100 µM) for 20 min, and 10 µL of propidium iodide (6 µM) for 10 min, and then analyzed by flow cytometry. To evaluate the transfection rates, sperm cells, after incubation, were separated from non-associated exogenous DNA by 2.5% gel electrophoresis. DNA (genomic and exogenous) was extracted and association rates obtained by real-time PCR. Data were submitted to ANOVA and compared by Tukey's test (P ≤ 0.05). The number of viable, apoptotic, oncosis, or in initial apoptosis/late oncosis spermatozoa incubated with different concentrations or sequences of exogenous DNA did not differ among groups. In Experiment 1, a higher DNA association with sperm cells was observed in the 5.5 kb sequence in comparison with the 2.2 and 8.5 kb. In Experiment 2, the 8.5 kb sequence had the lower association with the spermatozoa in comparison with the 2.2 kb and 5.5 kb. In Experiment 3, there was a higher interaction of the AT sequence when compared to IN and GC sequences. Reference data suggest that big sequences of exogenous DNA have advantages in the interaction with spermatozoa. The present work is the first one to show that the advantage of the big sequences on interaction became a disadvantage in relation to the ability of these cells to internalize this DNA. Table 1. Quantification of different exogenous DNA associated to sperm cells Financial support was provided by FAPESP 03/10234-7 and 03/07456-8.

scholarly journals Localization of phosphatidylserine in boar sperm cell membranes during capacitation and acrosome reaction

Reproduction ◽  
2005 ◽  
Vol 130 (5) ◽  
pp. 615-626 ◽  
Author(s):  
Anke Kurz ◽  
Dagmar Viertel ◽  
Andreas Herrmann ◽  
Karin Müller
Keyword(s):  
Plasma Membrane ◽  
Sperm Cell ◽  
Acrosome Reaction ◽  
Cell Membranes ◽  
Plasma Membranes ◽  
Sperm Cells ◽  
Cytoplasmic Localization ◽  
Lipid Asymmetry ◽  
Viable Cells ◽  
Boar Sperm

One of the essential properties of mammalian, including sperm, plasma membranes is a stable transversal lipid asymmetry with the aminophospholipids, phosphatidylserine (PS) and phosphatidylethanolamine (PE), typically in the inner, cytoplasmic leaflet. The maintenance of this nonrandom lipid distribution is important for the homeostasis of the cell. To clarify the relevance of lipid asymmetry to sperm function, we have studied the localization of PS in boar sperm cell membranes. By using labeled annexin V as a marker for PS and propidium iodide (PI) as a stain for nonviable cells in conjunction with different methods (flow cytometry, fluorescence and electron microscopy), we have assessed the surface exposure of PS in viable cells during sperm genesis, that is, before and during capacitation as well as after acrosome reaction. An approach was set up to address also the presence of PS in the outer acrosome membrane. The results show that PS is localized in the cytoplasmic leaflet of the plasma membrane as well as on the outer acrosome membrane. Our results further indicate the cytoplasmic localization of PS in the postacrosomal region. During capacitation and acrosome reaction of spermatozoa, PS does not become exposed on the outer surface of the viable cells. Only in a subpopulation of PI-positive sperm cells does PS became accessible upon capacitation. The stable cytoplasmic localization of PS in the plasma membrane, as well as in the outer acrosome membrane, is assumed to be essential for a proper genesis of sperm cells during capacitation and acrosome reaction.

DIFFERENCES OF SPERMATHECA AND SPERM CELLS IN THE GENERA DITYLENCHUS FILIPJEV, 1936 AND TYLENCHUS BASTIAN, 1865 (TYLENCHIDAE:NEMATODA)

1967 ◽  
Vol 45 (1) ◽  
pp. 27-30 ◽  
Author(s):  
Liang-Yu Wu
Keyword(s):  
Sperm Cell ◽  
Tubular Structure ◽  
Sperm Cells ◽  
Structural Differences ◽  
Dense Nucleus

Structural differences in the spermatheca and sperm cells of Ditylenchus and Tylenchus were found to be of significant value in the separation of these two genera. In Ditylenchus, the spermatheca is a long tubular structure located between the uterus and the oviduct. The sperm cell consists of two parts: a dense nucleus and a large translucent vesicle. In Tylenchus, the spermatheca, when present, is in the form of a diverticulum of various shapes, arising at the junction of the uterus and the oviduct. The translucent vesicle is absent within the sperm cell.

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