Asterosap, an Egg Jelly Peptide, Elevate Intracellular Ca<sup>2+</sup> and Activate the Motility of Spermatozoa

Components from the outer envelopes of the egg that influence the flagellar beating and acrosome reaction of spermatozoa are regulated by ion flux across the plasma membrane. Asterosap, a sperm-activating peptide from the starfish egg jelly layer, causes a transient increase in intracellular cyclic GMP (cGMP) through the activation of the asterosap receptor, a guanylyl cyclase (GC), and causes an increase in intracellular Ca2+. Here we describe the pathway of asterosap-induced Ca2+ elevation using different Ca2+ channel antagonists. Fluo-4 AM, a cell permeable Ca2+ sensitive dye was used to determine the channel caused by the asterosap-induced Ca2+ elevation in spermatozoa. Different L-type Ca2+ channel antagonists, a non specific Ca2+ channel antagonist (nickel chloride), and a store-operated Ca2+ channel (SOC) antagonist do not show any significant response on asterosap-induced Ca2+ elevation, whereas KB-R7943, a selective inhibitor against Na+/Ca2+ exchanger (NCX) inhibited effectively. We also analyzed the flagellar movement of spermatozoa in artificial seawater (ASW) containing the asterosap at 100 nM ml?1. We found that spermatozoa swam vigorously with more symmetrical flagellar movement in asterosap than in ASW and KB-R7943 significantly inhibited the flagellar movement.DOI: http://dx.doi.org/10.3329/pa.v19i1.17358 Progress. Agric. 19(1): 79 - 88, 2008

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Guanylyl cyclase and cGMP-specific phosphodiesterase participate in the acrosome reaction of starfish sperm

Zygote ◽

10.1017/s0967199404002977 ◽

2004 ◽

Vol 12 (4) ◽

pp. 345-355 ◽

Cited By ~ 1

Author(s):

Osamu Kawase ◽

Seiichi Ueno ◽

Hiroyuki Minakata ◽

Motonori Hoshi ◽

Midori Matsumoto

Keyword(s):

Guanylyl Cyclase ◽

Acrosome Reaction ◽

Transient Increase ◽

Asterias Amurensis ◽

Intracellular Cgmp ◽

Intracellular Ca ◽

Egg Jelly ◽

Three Components

In the starfish, Asterias amurensis, the cooperation of three components of the egg jelly, i.e. ARIS (acrosome reaction-inducing substance), Co-ARIS and asterosap, is responsible for inducing the acrosome reaction. Experimentally, ARIS and asterosap are sufficient for the induction. However, when sperm are treated only with asterosap, they become unresponsive to the egg jelly to undergo the reaction. In this study, we analysed the mechanism of the acrosome reaction, using sperm inactivation by asterosap as a clue. Asterosap causes a rapid and transient increase in intracellular cGMP through the activation of the asterosap receptor, a guanylyl cyclase, and causes an increase in intracellular Ca2+. When sperm were pretreated with asterosap, the guanylyl cyclase seemed to be inactivated irreversibly by dephosphorylation. They were still responsive to ARIS but no longer to asterosap. However, in the presence of IBMX or zaprinast, inhibitors against phosphodiesterases (PDEs), they retained their capacity to undergo the acrosome reaction in response to the egg jelly or ARIS alone. IBMX and zaprinast suppressed the intracellular catabolism of cGMP, but not of cAMP. These results suggest that guanylyl cyclase and cGMP-specific, IBMX- and zaprinast-susceptible PDEs are involved in the regulation of the acrosome reaction.

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Ca2+ channels from the sea urchin sperm plasma membrane.

The Journal of General Physiology ◽

10.1085/jgp.95.2.273 ◽

1990 ◽

Vol 95 (2) ◽

pp. 273-296 ◽

Cited By ~ 46

Author(s):

A Liévano ◽

E C Vega-SaenzdeMiera ◽

A Darszon

Keyword(s):

Plasma Membrane ◽

Sea Urchin ◽

Acrosome Reaction ◽

Main Channel ◽

Open Probability ◽

Boltzmann Function ◽

Sperm Plasma Membrane ◽

Egg Jelly ◽

Sea Urchin Sperm ◽

Ca2 Channels

Ca2+ influx across the sea urchin sperm plasma membrane is a necessary step during the egg jelly-induced acrosome reaction. There is pharmacological evidence for the involvement of Ca2+ channels in this influx, but their presence has not been directly demonstrated because of the small size of this cell. Sea urchin sperm Ca2+ channels are being studied by fusing isolated plasma membranes into planar lipid bilayers. With this strategy, a Ca2+ channel has been detected with the following characteristics: (a) the channel exhibits a high mainstate conductance (gamma MS) of 172 pS in 50 mM CaCl2 solutions with voltage-dependent decaying to smaller conductance states at negative Em; (b) the channel is blocked by millimolar concentrations of Cd2+, Co2+, and La3+, which also inhibit the egg jelly-induced acrosome reaction; (c) the gamma MS conductance sequence for the tested divalent cations is the following: Ba2+ greater than Sr2+ greater than Ca2+; and (d) the channel discriminates poorly for divalent over monovalent cations (PCa/PNa = 5.9). The sperm Ca2+ channel gamma MS rectifies in symmetrical 10 mM CaCl2, having a maximal slope conductance value of 94 pS at +100 mV applied to the cis side of the bilayer. Under these conditions, a different single-channel activity of lesser conductance became apparent above the gamma MS current at positive membrane potentials. Also in 10 mM Ca2+ solutions, Mg2+ permeates through the main channel when added to the cis side with a PCa/PMg = 2.9, while it blocks when added to the trans side. In 50 mM Ca2+ solutions, the gamma MS open probability has values of 1.0 at voltages more positive than -40 mV and decreases at more negatives potentials, following a Boltzmann function with an E0.5 = -72 mV and an apparent gating charge value of 3.9. These results describe a novel Ca2(+)-selective channel, and suggest that the main channel works as a single multipore assembly.

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Differential effects of soluble and particulate guanylyl cyclase on Ca2+ sensitivity in airway smooth muscle

Journal of Applied Physiology ◽

10.1152/jappl.2002.92.1.257 ◽

2002 ◽

Vol 92 (1) ◽

pp. 257-263 ◽

Cited By ~ 37

Author(s):

Edwin H. Rho ◽

William J. Perkins ◽

Robert R. Lorenz ◽

David O. Warner ◽

Keith A. Jones

Keyword(s):

Smooth Muscle ◽

Airway Smooth Muscle ◽

Guanylyl Cyclase ◽

Soluble Guanylyl Cyclase ◽

Rightward Shift ◽

Muscarinic Stimulation ◽

Intracellular Ca ◽

A Cell ◽

The Relationship ◽

Stimulation Of

Maximal relaxation of airway smooth muscle (ASM) in response to atrial natriuretic peptide (ANP), which stimulates particulate guanylyl cyclase (pGC), is less than that produced by nitric oxide (NO) and other compounds that stimulate soluble guanylyl cyclase (sGC). We hypothesized that stimulation of pGC relaxes ASM only by decreasing intracellular Ca2+ concentration ([Ca2+]i), whereas stimulation of sGC decreases both [Ca2+]i and the force developed for a given [Ca2+]i (i.e., the Ca2+ sensitivity) during muscarinic stimulation. We measured the relationship between force and [Ca2+]i (using fura 2) under control conditions (using diltiazem to change [Ca2+]i) and during exposure to ANP, diethylamine-NO (DEA-NO), sodium nitroprusside (SNP), and the Sp diastereoisomer of β-phenyl-1, N 2-etheno-8-bromoguanosine-3′,5′-cyclic monophosphorothionate ( Sp-8-Br-PET-cGMPS), a cell-permeant analog of cGMP. Addition of DEA-NO, SNP, or Sp-8-Br-PET-cGMPS decreased both [Ca2+]i and force, causing a significant rightward shift of the force-[Ca2+]irelationship. In contrast, with ANP exposure, the force-[Ca2+]i relationship was identical to control, such that ANP produced relaxation solely by decreasing [Ca2+]i. Thus, during muscarinic stimulation, stimulation of pGC relaxes ASM exclusively by decreasing [Ca2+]i, whereas stimulation of sGC decreases both [Ca2+]i and Ca2+sensitivity.

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Molecular physiology and pathology of Ca2+-conducting channels in the plasma membrane of mammalian sperm

Reproduction ◽

10.1530/rep.1.00478 ◽

2005 ◽

Vol 129 (3) ◽

pp. 251-262 ◽

Cited By ~ 27

Author(s):

Ricardo Felix

Keyword(s):

Plasma Membrane ◽

Acrosome Reaction ◽

Current Evidence ◽

Molecular Physiology ◽

Mammalian Sperm ◽

Fertilizing Ability ◽

Intracellular Ca ◽

Gene Defects ◽

Sperm Fertilizing Ability ◽

Sperm Functions

Current evidence indicates that mechanisms controlling the intracellular Ca2+concentration play pivotal roles in determining sperm fertilizing ability. Multiple Ca2+-permeable channels have been identified and characterized in the plasma membrane and in the acrosome membrane of mammalian sperm. This review summarizes the recent findings and assesses the evidence suggesting that these channels play roles in controlling a host of sperm functions ranging from motility to the acrosome reaction, and describes recent advances in the identification of the underlying gene defects of inherited sperm Ca2+channelopathies.

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Measurement of plasma membrane and mitochondrial potentials in sea urchin sperm. Changes upon activation and induction of the acrosome reaction.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)89832-5 ◽

1984 ◽

Vol 259 (22) ◽

pp. 13914-13922 ◽

Cited By ~ 3

Author(s):

R W Schackmann ◽

R Christen ◽

B M Shapiro

Keyword(s):

Plasma Membrane ◽

Sea Urchin ◽

Acrosome Reaction ◽

Sea Urchin Sperm

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Evidence for the activation of two different Ca2+ channels during the egg jelly-induced acrosome reaction of sea urchin sperm

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)47155-x ◽

1989 ◽

Vol 264 (33) ◽

pp. 19593-19599

Author(s):

A Guerrero ◽

A Darszon

Keyword(s):

Sea Urchin ◽

Acrosome Reaction ◽

Egg Jelly ◽

Sea Urchin Sperm ◽

Ca2 Channels

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Putative PmrA and PmcA are important for normal growth, morphogenesis and cell wall integrity, but not for viability in Aspergillus nidulans

Microbiology ◽

10.1099/mic.0.080119-0 ◽

2014 ◽

Vol 160 (11) ◽

pp. 2387-2395 ◽

Cited By ~ 7

Author(s):

Hechun Jiang ◽

Feifei Liu ◽

Shizhu Zhang ◽

Ling Lu

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Aspergillus Nidulans ◽

Normal Growth ◽

Cell Wall Integrity ◽

Plasma Membrane Atpase ◽

Growth Defects ◽

Double Deletion ◽

Intracellular Ca ◽

P Type

P-type Ca2+-transporting ATPases are Ca2+ pumps, extruding cytosolic Ca2+ to the extracellular environment or the intracellular Ca2+ store lumens. In budding yeast, Pmr1 (plasma membrane ATPase related), and Pmc1 (plasma membrane calcium-ATPase) cannot be deleted simultaneously for it to survive in standard medium. Here, we deleted two putative Ca2+ pumps, designated AnPmrA and AnPmcA, from Aspergillus nidulans, and obtained the mutants ΔanpmrA and ΔanpmcA, respectively. Then, using ΔanpmrA as the starting strain, the promoter of its anpmcA was replaced with the alcA promoter to secure the mutant ΔanpmrAalcApmcA or its anpmcA was deleted completely to produce the mutant ΔanpmrAΔpmcA. Different from the case in Saccharomyces cerevisiae, double deletion of anpmrA and anpmcA was not lethal in A. nidulans. In addition, deletion of anpmrA and/or anpmcA had produced growth defects, although overexpression of AnPmc1 in ΔanpmrAalcApmcA could not restore the growth defects that resulted from the loss of AnPmrA. Moreover, we found AnPmrA was indispensable for maintenance of normal morphogenesis, especially in low-Ca2+/Mn2+ environments. Thus, our findings suggest AnPmrA and AnPmcA might play important roles in growth, morphogenesis and cell wall integrity in A. nidulans in a different way from that in yeasts.

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Progesterone treatment of boar spermatozoa improves male pronuclear formation after intracytoplasmic sperm injection into porcine oocytes

Zygote ◽

10.1017/s0967199402002137 ◽

2002 ◽

Vol 10 (2) ◽

pp. 95-104 ◽

Cited By ~ 16

Author(s):

Mike Katayama ◽

Takashi Miyano ◽

Masashi Miyake ◽

Seishiro Kato

Keyword(s):

Plasma Membrane ◽

Intracytoplasmic Sperm Injection ◽

Acrosome Reaction ◽

Sperm Chromatin ◽

Oocyte Activation ◽

Freezing And Thawing ◽

Chromatin Decondensation ◽

Progesterone Treatment ◽

Pronuclear Formation ◽

Boar Spermatozoa

Boar spermatozoa were prepared for intracytoplasmic sperm injection (ICSI) by two different treatments to facilitate sperm chromatin decondensation and improve fertilisation rates after ICSI in pigs: spermatozoa were either frozen and thawed without cryoprotectants, or treated with progesterone. Morphological changes of the sperm heads after the treatments were examined and then the activation of oocytes and the transformation of the sperm nucleus following ICSI were assessed. After freezing and thawing, the plasma membrane and acrosomal contents over the apical region of sperm head were lost in all the spermatozoa. Following treatment with 1 mg/ml progesterone, the acrosome reaction was induced in 61% of spermatozoa. After injection of three types of spermatozoa, non-treated spermatozoa and progesterone-treated (i.e. acrosome-reacted) spermatozoa induced oocyte activation, but frozen-thawed spermatozoa induced oocyte activation at a significantly lower rate. Sixty-two per cent of sperm heads remained orcein-negative for 6 h, however, resulting in delayed sperm chromatin decondensation and low male pronuclear formation in the oocytes injected with a non-treated spermatazoon. Since the treatments of freezing and thawing and progesterone for spermatozoa accelerated the initial change in sperm chromatin and the latter treatment induced oocyte activation earlier, it is considered that the delay in oocyte activation and decondensation of sperm chromatin after injection of non-treated spermatozoa is caused by the existence of the sperm plasma membrane. These results show that progesterone treatment efficiently induces the acrosome reaction in boar spermatozoa without destroying their potency for oocyte activation, and the induction of the acrosome reaction results in the promotion of male pronuclear formation after ICSI.

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A cell-free assay for the insertion of a viral glycoprotein into the plasma membrane.

The Journal of Cell Biology ◽

10.1083/jcb.103.5.1829 ◽

1986 ◽

Vol 103 (5) ◽

pp. 1829-1835 ◽

Cited By ~ 13

Author(s):

P G Woodman ◽

J M Edwardson

Keyword(s):

Influenza Virus ◽

Plasma Membrane ◽

Trichloroacetic Acid ◽

Plasma Membranes ◽

Semliki Forest Virus ◽

Fusion Reaction ◽

Viral Glycoprotein ◽

Acetylneuraminic Acid ◽

Donor And Acceptor ◽

A Cell

A cell-free assay has been developed for the delivery of influenza virus neuraminidase to the plasma membrane. Two types of postnuclear supernatant, which acted as donor and acceptor of the enzyme, were prepared from baby hamster kidney cells. Donor preparations were obtained from cells infected with influenza virus and containing neuraminidase en route to the plasma membrane. Acceptor preparations were obtained from cells containing, bound to their plasma membranes, Semliki Forest virus with envelope glycoproteins bearing [3H]N-acetylneuraminic acid. Fusion between vesicles from these two preparations permits access of the enzyme to its substrate, which results in the release of free [3H]N-acetylneuraminic acid. This release was detected through the transfer of radioactivity from a trichloroacetic acid-insoluble to a trichloroacetic acid-soluble fraction. An ATP-dependent component of release was found, which appears to be a consequence of vesicle fusion. This component was enhanced when the donor was prepared from cells in which the enzyme had been concentrated in a compartment between the Golgi complex and the plasma membrane, which indicates that a specific exocytic fusion event has been reconstituted. The extent of fusion is greatly reduced by pre-treatment of donor and acceptor preparations with trypsin, which points to the involvement of proteins in the fusion reaction.

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