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Topic: Acrosome


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In the News (Mon 22 Jul 19)

  
  Acrosome Reaction Animation   (Site not responding. Last check: 2007-10-22)
This causes an influx of Ca++ into the sperm head and an increase in pHi.
The Ca++ increase causes the acrosome vesicle (green) to fuse with the plasma membrane of the sperm and the vesicle undergoes exocytosis.
The increase in pHi causes the actin (pink) to go from the globular state to the filamentous state pushing out the acrosomal process and exposing
www.luc.edu /depts/biology/dev/acrosanm.htm   (78 words)

  
 Mammalian acrosome reaction
The picture of fertilization had been that the acrosome reaction should occur prior to binding (as it does in sea urchins) and that the mammalian sperm would use the enzymes from the acrosome to lyse its way through the cumulus.
Evidence that the crosslinking of sperm receptors for ZP3 is necessary to initiate the acrosome reaction of mouse sperm.
Evidence for the role of a guanosine nucleotidebinding regulatory protein in the zona pellucidainduced mouse sperm acrosome reaction.
zygote.swarthmore.edu /fert5.html   (889 words)

  
 Tribulus terrestris & Protodioscin Study - Acrosome Reaction & Sperm Motility
The percentage of the sperm with normal acrosome reaction was also increased, whereas the percentage of immotile sperm decreased significantly.
Another useful analysis of sperm viability is the efficiency of acrosome reaction, which is extremely important for fertilization in vivo and in vitro.
The zona pellucida-induced acrosome reaction of human spermatozoa is mediated by protein kinases.
www.libilov.com /en/clinical_studies/study_Setiawan_1996.htm   (3512 words)

  
 LLU Center for Fertility and In Vitro Fertilization - spermac protocol
Score as acrosomal-reacted/abnormal acrosome if the acrosomal region is pink (sperm #2), or it is green but the semi-circle band is either broken-up, discontinuous, vesiculated, botched, missing band, or fuzzy, without a distinct dark-green band at the tip of sperm head (sperm #3).
Since the acrosome is being analyzed rather than the morphology, all shapes of sperm that are "acrosome-intact" will be counted even though they appear as pyriform, amorphous, oval, etc.
To determine the percentage of acrosome reaction in response to a specific treatment as in THE ARIC TEST, or after a period of incubation, prepare the sperm smear before and after the treatment.
www.llu.edu /lluhc/fertility/spermac.html   (1328 words)

  
 A Functional Cytochrome P450 Lanosterol 14{alpha}-Demethylase CYP51 Enzyme in the Acrosome: Transport through the Golgi ...
isolated acrosomal membrane from the bull and ram sperm.
B, 1, immunoblot analysis of bull acrosomal membranes; 2, Coomassie-stained immunoprecipitate of 1; 3, detection of glycosylated proteins from 2.
catalyzed conversion of androgens to estrogens, and the acrosomal,
endo.endojournals.org /cgi/content/full/145/3/1419   (5113 words)

  
 UNSW Embryo- Acrosome OMIM ENTRY 102530
(1977) observed acrosome malformations of spermatids and spermatozoa in the testes of 2 infertile males who were investigated by light and electron microscopy.
Defective differentiation of the acrosome granule in spermatids appeared to be responsible for the malformation of mature spermatozoa.
In Friesian bulls, a characteristic defect of the acrosome ('knobbed' spermatozoa) associated with sterility appears to be autosomal recessive.
embryology.med.unsw.edu.au /OMIMfind/fert/102530.htm   (534 words)

  
 Angiotensin II induces acrosomal exocytosis in bovine spermatozoa -- Gur et al. 275 (1): 87 -- AJP - Endocrinology and ...
the release of the acrosomal hydrolytic enzymes (5, 31).
The acrosome reaction was determined by measuring the release of acrosin from bovine spermatozoa and by staining with PSA.
Evidence for the role of cyclooxygenase (prostaglandin synthetase) and prostaglandins in the sperm acrosome reaction and fertilization.
ajpendo.physiology.org /cgi/content/full/275/1/E87   (3431 words)

  
 Sperm receptor
Both are shed, resulting in the exposure of the inner acrosomal membrane and subsequent release of acrosomal enzymes.
Using EGTA to prevent the acrosome reaction and the ionophore A23187 to induce the event, acrosome-reacted and acrosome-intact sperm were obtained from mice.
The prevailing view is that this binding may actually reflect binding of ZP2 to the inner acrosomal membrane of sperm heads in the process of undergoing the acrosome reaction.
www.ucalgary.ca /~browder/zonafunction.html   (994 words)

  
 Zona pellucida-induced acrosome reaction in human sperm: dependency on activation of pertussis toxin-sensitive Gi ...
Zona pellucida-induced acrosome reaction in human sperm: dependency on activation of pertussis toxin-sensitive Gi protein and extracellular calcium, and priming effect of progesterone and follicular fluid -- Schuffner et al.
The acrosome reaction is a prerequisite for fertilization in
Tesarik, J., Carrera, A. and Mendoza, C. (1993) Differential sensitivity of progesterone and zona pellucida-induced acrosome reactions to pertussis toxin.
molehr.oxfordjournals.org /cgi/content/full/8/8/722   (5526 words)

  
 Acrosome Reaction   (Site not responding. Last check: 2007-10-22)
The acrosome reaction is a change in the sperm that is common to many higher animals.
In the sea urchin, contact with egg jelly initiates the acrosome reaction, which is a calcium-mediated process.
The acrosomal vesicle (green) fuses with the plasma membrane, releasing enzymes from the tip of the sperm that aid digestion of egg jelly.
worms.zoology.wisc.edu /urchins/SUfert_acrosome.html   (125 words)

  
 Marie-France Pfenninger, Ph.D.   (Site not responding. Last check: 2007-10-22)
The acrosome is a cap-like vesicular organelle located in the anterior two-thirds of the sperm head.
The content of the acrosome is released by exocytosis during the acrosomal reaction, as the spermatozoon begins to penetrate the egg investments.
Spermatozoa devoid of the acrosome or with the acrosome intact are unfertile, as are sperm with low levels of hydrolytic enzymes.
www.uchsc.edu /bsp/profiles/pfenningerm.htm   (290 words)

  
 Rab3A Triggers the Acrosome Reaction in Permeabilized Human Spermatozoa -- Yunes et al. 62 (4): 1084 -- Biology of ...
The percentage of spontaneous acrosome reactions observed under the control condition (incubation in the absence of acrosome reaction stimulatory reagents) was subtracted from all values, and it ranged between 19% and 30%.
The percentage of spontaneous acrosome reactions observed under the control condition (incubation in the absence of any reagent) was subtracted from all values, and it ranged between 20% and 30%.
The percentage of spontaneous acrosome reactions observed under the control condition (incubation in the absence of any reagent) was subtracted from all values, and it ranged between 21% and 34%.
www.biolreprod.org /cgi/content/full/62/4/1084   (4301 words)

  
 Disruption of Mouse CD46 Causes an Accelerated Spontaneous Acrosome Reaction in Sperm -- Inoue et al. 23 (7): 2614 -- ...
The acrosome reaction is a prerequisite for sperm to fertilize
Sperm from beta 1,4-galactosyltransferase-null mice are refractory to ZP3-induced acrosome reactions and penetrate the zona pellucida poorly.
Alkalinization of acrosome measured by GFP as a pH indicator and its relation to sperm capacitation.
mcb.asm.org /cgi/content/full/23/7/2614   (5584 words)

  
 Brain Synaptic Junctional Proteins at the Acrosome of Rat Testicular Germ Cells -- Redecker et al. 51 (6): 809 -- ...   (Site not responding. Last check: 2007-10-22)
In addition to acrosomal labeling of round spermatids, immunoreactivity for ProSAP1/Shank2 is present in the cell cortex of spermatogonia/young spermatocytes (arrows) that are situated in two adjacent tubules (C).
Distinct immunoreactivity for caldendrin, ProSAP2/Shank3, and VIAAT is visible at the acrosomes (arrows).
Ward CR, Faundes D, Foster LA (1999) The monomeric GTP binding protein, rab3a, is associated with the acrosome in mouse sperm.
www.jhc.org /cgi/content/full/51/6/809   (4090 words)

  
 Phospholipase C{delta}4 is required for Ca2+ mobilization essential for acrosome reaction in sperm -- Fukami et al. 161 ...   (Site not responding. Last check: 2007-10-22)
acrosome reaction was not disturbed in mutant sperm and occurred
in sperm occurs primarily in the acrosome and in the
Spatiotemporal characterization of intracellular Ca rise during the acrosome reaction of mammalian spermatozoa induced by zona pellucida.
www.jcb.org /cgi/content/full/161/1/79   (5096 words)

  
 Haprin, a Novel Haploid Germ Cell-specific RING Finger Protein Involved in the Acrosome Reaction -- Kitamura et al. 278 ...
It was localized in the acrosomal region of elongated
of Haprin inhibited the acrosome reaction in permeabilized sperm.
a key role in the acrosome reaction and fertilization.
www.jbc.org /cgi/content/abstract/278/45/44417   (389 words)

  
 Ca2+ Entry through Store-operated Channels in Mouse Sperm Is Initiated by Egg ZP3 and Drives the Acrosome Reaction -- ...   (Site not responding. Last check: 2007-10-22)
, AR, and AR are the levels of acrosome reactions at 0 min, at 30 min in the presence of AN1043, and at 30 min in the absence of AN1043, respectively.
The derived IC for inhibition of the acrosome reaction was 1.1 ± 0.2 µM. Data in A and B represent the means (±SD) of triplicate experiments, with 200 sperm examined at each time or concentration point in each experiment.
Tesarik, J., Carreras, A., and Mendoza, C. Differential sensitivity of progesterone- and zona pellucida-induced acrosome reactions to pertussis toxin.
www.molbiolcell.org /cgi/content/full/11/5/1571   (7386 words)

  
 The significance of the ionophore-challenged acrosome reaction in the prediction of successful outcome of controlled ...   (Site not responding. Last check: 2007-10-22)
Avrech, O., Fisch, B. and Shalgi, R. (1997) Acrosomal status of human spermatozoa after follicular fluid or calcium ionophore challenge in relation to semen parameters and fertilizing capacity in vitro.
Henkel, R., Muller, C., Miska, W., Gips, H. and Schill, W.B. (1993) Determination of the acrosome reaction in the human spermatozoa is predictive of fertilization in vitro.
Takahashi, K., Wetzels, A.M., Goverde, H.J., Bastaans, B.A., Janssen, H.J. and Rolland, R. (1992) The kinetics of the acrosome reaction of human spermatozoa and its correlation with in vitro fertilization.
humrep.oxfordjournals.org /cgi/content/full/18/3/534   (3748 words)

  
 Control of Membrane Fusion During Spermiogenesis and the Acrosome Reaction -- Ramalho-Santos et al. 67 (4): 1043 -- ...
During this process the Golgi apparatus migrates toward the opposite pole of the nascent acrosome, and the acrosomal vesicle lies underneath the plasma membrane (4, 5).
The AR is the exocytic event by which the acrosome fuses with the sperm plasma membrane and exposes its contents to the extracellular milieu.
In vitro fertilization and the sperm acrosome reaction in the hamster.
www.biolreprod.org /cgi/content/full/67/4/1043   (6760 words)

  
 Comparison of acrosome reaction-inducing activities of human cumulus oophorus, follicular fluid and ionophore A23187 in ...
Comparison of acrosome reaction-inducing activities of human cumulus oophorus, follicular fluid and ionophore A23187 in human sperm populations of proven fertilizing ability in vitro
Significant differences in the frequency of spontaneous and induced acrosome reactions (identified by electron microscopy) were detected between 5 individual sperm samples.
Maximal stimulation of the acrosome reaction was achieved with ionophore A23187, no differences being detected between the two preincubation times used (5 and 15 h).
www.reproduction-online.org /cgi/content/abstract/74/2/383   (475 words)

  
 Intracellular sodium changes during the speract response and the acrosome reaction in sea urchin sperm -- ...
The egg-jelly component that induces the acrosome reaction (AR), a crucial event for fertilization, is a fucose sulphated glycoconjugate (FSG; Vacquier, 1998).
As anticipated, fluorescence microscopy revealed that the SBFI fluorescence was mainly in the cytoplasm, and the remainder mostly in the mitochondria and acrosome (data not shown).
The fucose sulfate polymer of egg jelly binds to sperm REJ and is the inducer of the sea urchin sperm acrosome reaction.
jp.physoc.org /cgi/content/full/546/1/89   (6964 words)

  
 Remodeling of the Actin Cytoskeleton During Mammalian Sperm Capacitation and Acrosome Reaction -- Brener et al. 68 (3): ...
Polymerization of actin during capacitation and depolymerization in the acrosome reaction.
Ram spermatozoa were incubated in capacitation medium and the amount of F-actin and the ability of the cells to undergo an A23187-induced acrosome reaction were determined at various times.
Hernandez-Gonzalez EO, Lecona-Valera AN, Escobar-Herrera J, Mujica A. Involvement of an F-actin skeleton on the acrosome reaction in guinea pig spermatozoa.
www.biolreprod.org /cgi/content/full/68/3/837   (4998 words)

  
 Progesterone promotes the acrosome reaction in capacitated human spermatozoa as judged by flow cytometry and CD46 ...
The acrosome reaction is a necessary prerequisite for spermatozoa
The acrosome reaction was induced in capacitated spermatozoa
Suarez, S.S., Wolf, D.P. and Meizel, S. (1986) Induction of the acrosome reaction in human spermatozoa by a fraction of human follicular fluid.
molehr.oxfordjournals.org /cgi/content/full/5/6/507   (3792 words)

  
 Acrosome   (Site not responding. Last check: 2007-10-22)
It is a cap-like structure derived from the Golgi apparatus.
In Eutherian mammals, acrosome formation is completed during testicular maturation.
The acrosome contains digestive enzymes (including hyaluronidase and acrosin) needed to penetrate the zona pellucida covering the ovum.
www.worldhistory.com /wiki/A/Acrosome.htm   (134 words)

  
 Haprin, a Novel Haploid Germ Cell-specific RING Finger Protein Involved in the Acrosome Reaction -- Kitamura et al. 278 ...
The acrosome reaction was induced with calcium ionophore, and sperm samples were stained with anti-Haprin antiserum and Texas Red-labeled secondary antibody (A).
C, acrosome reaction was induced with calcium ionophore.
Haprin is localized to the cytoplasmic region of the sperm head and associated with the cytoskeleton.
www.jbc.org /cgi/content/full/278/45/44417   (4468 words)

  
 Activation of Protein Kinase A During Human Sperm Capacitation and Acrosome Reaction -- Lefièvre et al. 23 (5): ...
acrosome reaction induced by A23187 was associated with increases
Protein tyrosine phosphorylation, hyperactivation and progesterone-induced acrosome reaction are enhanced in IVF media: an effect that is not associated with an increase in protein kinase A activation
Role of actin cytoskeleton in mammalian sperm capacitation and the acrosome reaction
www.andrologyjournal.org /cgi/content/abstract/23/5/709   (594 words)

  
 Acroplaxome, an F-Actin-Keratin-containing Plate, Anchors the Acrosome to the Nucleus during Shaping of the Spermatid ...   (Site not responding. Last check: 2007-10-22)
The acrosome vesicle is lodged in a shallow depression of the nucleus (arrows) where the density of the acroplaxome is seen.
The inner acrosomal membrane-associated plaque (dashed box) at the leading edge of the acroplaxome (arrow) is detected.
The K5 filament bundle is attached to the dense acrosomal plaque, whose constituents are presently unknown.
www.molbiolcell.org /cgi/content/full/14/11/4628   (6243 words)

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