Calcium oscillations in human oocytes

Swann, Karl; Lawrence, Yvonne

doi:10.1093/molehr/2.6.388

Cited by 14 publications

(6 citation statements)

References 17 publications

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“…1A) (GenBank TM accession number AF435950) or s-PLC lacking 110 amino acid residues from the N terminus (AK006672) was prepared using PCR techniques, fused with Venus (19) in the C terminus, and subcloned into pBluescript II SK(ϩ). The methods were the same as described previously (4).…”

Section: Methodsmentioning

confidence: 99%

“…PLC is specifically expressed in the sperm (2) and induces repetitive increase in [Ca 2ϩ ] i called Ca 2ϩ oscillations and subsequent early embryonic development when expressed in mouse eggs by injection of RNA encoding PLC (2,3). In mammalian fertilization, accumulated evidence indicates that a cytosolic sperm factor is driven into the ooplasm upon sperm egg fusion and induces Ca 2ϩ oscillations (4,5), which are caused by Ca 2ϩ release from the endoplasmic reticulum mainly through type 1 IP 3 receptor (6) and are a pivotal signal for egg activation characterized by resumption of the second meiosis and formation of PN (5). PLC is a strong candidate of the sperm factor, because 1) fertilization-like Ca 2ϩ oscillations are produced by PLC expressed in a mouse egg at an estimated level comparable to the content in single mouse sperm (2,3).…”

Section: Plcmentioning

confidence: 99%

“…2) Injection of recombinant PLC into mouse eggs induces Ca 2ϩ oscillations as well (7). 3) Ca 2ϩ oscillation-inducing ability of sperm extract injected into eggs (4,8) is lost when pretreated with an antibody against PLC (2). 4) PLC content in the mouse sperm and the number of Ca 2ϩ spikes at fertilization are reduced by transgenic RNA interference of PLC (9).…”

Section: Plcmentioning

confidence: 99%

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The Role of X/Y Linker Region and N-terminal EF-hand Domain in Nuclear Translocation and Ca2+ Oscillation-inducing Activities of Phospholipase Cζ, a Mammalian Egg-activating Factor

Kuroda

Ito

Shikano

et al. 2006

Journal of Biological Chemistry

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Sperm-specific phospholipase C-zeta (PLC) causes intracellular Ca2؉ oscillations and thereby egg activation and is accumulated into the formed pronucleus (PN) when expressed in mouse eggs by injection of cRNA encoding PLC, which consists of four EF-hand domains (EF1-EF4) in the N terminus, X and Y catalytic domains, and C-terminal C2 domain. Those in the N terminus of EF1. Ca 2؉ oscillation-inducing activity was lost by the former mutation and was remarkably inhibited by the latter. A short sequence 374 -383 fused with Venus showed active translocation into the nucleus of COS-7 cells, but 296 -309 or 1-19 did not. Despite the presence of these special regions, both activities were deprived by deletion of not only EF1 but also EF2-4 or C2 domain. Thus, PLC is driven into the nucleus primarily by the aid of NLS and putative regulatory sites, but coordinated three-dimensional structure, possibly formed by a folding in the X/Y linker and close EF/C2 contact as in PLC␦1, seems to be required not only for enzymatic activity but also for nuclear translocation ability. PLC2 is a novel isozyme of PLC (the enzyme that hydrolyzes membrane PIP 2 into IP 3 and diacylglycerol) and a strong candidate of the mammalian sperm-derived egg-activating factor (1). PLC is specifically expressed in the sperm (2) and induces repetitive increase in [Ca 2ϩ ] i called Ca 2ϩ oscillations and subsequent early embryonic development when expressed in mouse eggs by injection of RNA encoding PLC (2, 3). In mammalian fertilization, accumulated evidence indicates that a cytosolic sperm factor is driven into the ooplasm upon sperm egg fusion and induces Ca 2ϩ oscillations (4, 5), which are caused by Ca 2ϩ release from the endoplasmic reticulum mainly through type 1 IP 3 receptor (6) and are a pivotal signal for egg activation characterized by resumption of the second meiosis and formation of PN (5). PLC is a strong candidate of the sperm factor, because 1) fertilization-like Ca 2ϩ oscillations are produced by PLC expressed in a mouse egg at an estimated level comparable to the content in single mouse sperm (2, 3). 2) Injection of recombinant PLC into mouse eggs induces Ca 2ϩ oscillations as well (7). 3) Ca 2ϩ oscillation-inducing ability of sperm extract injected into eggs (4, 8) is lost when pretreated with an antibody against PLC (2). 4) PLC content in the mouse sperm and the number of Ca 2ϩ spikes at fertilization are reduced by transgenic RNA interference of PLC (9). 5) PLC has such a high Ca 2ϩ sensitivity of PIP 2 -hydrolyzing activity that the enzyme can be active in the resting cells at ϳ100 nM Ca 2ϩ (7, 10), suitable for the sperm factor as the first stimulus in the egg cytoplasm at fertilization.Another important property of PLC is nuclear translocation ability. PLC expressed by RNA injection is accumulated into the formed PN (3,11,12). This is consistent with earlier observation that sperm-derived Ca 2ϩ oscillation-inducing activity is concentrated into PN formed several hours after fertilization, as examined by transfer of the oopla...

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Section: Methodsmentioning

confidence: 99%

Section: Plcmentioning

confidence: 99%

Section: Plcmentioning

confidence: 99%

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The Role of X/Y Linker Region and N-terminal EF-hand Domain in Nuclear Translocation and Ca2+ Oscillation-inducing Activities of Phospholipase Cζ, a Mammalian Egg-activating Factor

Kuroda

Ito

Shikano

et al. 2006

Journal of Biological Chemistry

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“…The [Ca 2ϩ ] i rises are a pivotal signal for egg activation and are responsible for early embryogenesis (2,3). Accumulated evidence suggests that Ca 2ϩ oscillations are induced by cytosolic sperm factor introduced into the ooplasm upon sperm-egg fusion (2,4). Therefore, the identification of the Ca 2ϩ oscillation-inducing sperm factor, which is the egg-activating sperm factor, is currently being studied as a central subject to elucidate the mechanisms of fertilization.…”

Section: ؉mentioning

confidence: 99%

“…The injection of RNA-encoding PLC into mouse eggs causes Ca 2ϩ oscillations and subsequent early embryonic development by expressed PLC at an estimated level comparable with the content in a single sperm (5). The Ca 2ϩ oscillation-inducing activity of sperm extract (4,6) is lost when pretreated with an antibody against PLC (5). Thus, PLC is considered a strong candidate of the sperm factor.…”

Section: ؉mentioning

confidence: 99%

Recombinant Phospholipase Cζ Has High Ca2+ Sensitivity and Induces Ca2+ Oscillations in Mouse Eggs

Kouchi

Fukami

Shikano

et al. 2004

Journal of Biological Chemistry

228

181

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] i rises are a pivotal signal for egg activation and are responsible for early embryogenesis (2, 3). Accumulated evidence suggests that Ca 2ϩ oscillations are induced by cytosolic sperm factor introduced into the ooplasm upon sperm-egg fusion (2, 4). Therefore, the identification of the Ca 2ϩ oscillation-inducing sperm factor, which is the egg-activating sperm factor, is currently being studied as a central subject to elucidate the mechanisms of fertilization. Recently, Saunders et al.(5) have reported a novel type of PLC (the enzyme that produces InsP 3 and diacylglycerol from membrane PtdInsP 2 ), PLC, which is specifically expressed in mammalian sperm. The injection of RNA-encoding PLC into mouse eggs causes Ca 2ϩ oscillations and subsequent early embryonic development by expressed PLC at an estimated level comparable with the content in a single sperm (5). The Ca 2ϩ oscillation-inducing activity of sperm extract (4, 6) is lost when pretreated with an antibody against PLC (5). Thus, PLC is considered a strong candidate of the sperm factor. To assure this possibility, it is primarily necessary to examine whether purified PLC protein induces Ca 2ϩ oscillations in the egg. It has been shown that PLC␤1 (7), -␥1 (8, 9), -␥2 (8), -␦1 (10), and -␦4 (7) are expressed in mammalian sperm and that recombinant PLC␤1, -␥1, -␥2, and -␦1 failed to cause Ca 2ϩ release in the ooplasm (11). PLC is the smallest PLC identified to date, lacking the N-terminal PH domain (Fig. 1A) (5) that is found in all isoforms of PLC␤, -␥, and -␦ and is the site for interaction with membrane phospholipids (12). Because PLC as well as PLC␦ lacks a regulatory domain such as the G protein-binding site of PLC␤ or the SH domain of PLC␥ for phosphorylation by tyrosine kinase, the activation mechanism of PLC and PLC␦ is unknown. Therefore, it is also necessary to access how PLC undergoes the active state for production of InsP 3 . Here we first show that recombinant PLC protein induces Ca 2ϩ oscillations in mouse eggs and that PLC possesses an extremely high Ca 2ϩ sensitivity in the PtdInsP 2 hydrolyzing activity to be active even at the resting state of cells. EXPERIMENTAL PROCEDURESCloning of PLC and PLC␦1-cDNA encoding full-length PLC (GenBank TM accession number AF435950) was cloned from a cDNA library originated from mouse testis mRNAs. PLC cDNA was amplified by PCR using Pfu polymerase and the following primers: forward, 5Ј-GAC AAGCGGCCCAGATCATG-3Ј; internal forward primer involving an EcoRI site, 5Ј-GGAATTCATATGGAAAGCCAACTTCATGAG-3Ј; re-* This work was supported by a grant-in-aid for general scientific research (Category B) (to S. M.) from the Japan Ministry of Education, Science, Sports, and Culture. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.The nucleotide sequence (s)

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The thiol reagent, thimerosal, irreversibly inhibits meiosis reinitiation in mouse oocyte when applied during a very early and narrow temporal window: A pharmacological analysis

Alexandre

Delsinne

Goval

2003

Molecular Reproduction Devel

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The effect of the sulfhydryl reagent, thimerosal (TMS) on meiosis resumption in germinal vesicle (GV)-stage denuded mouse oocytes was studied. It irreversibly inhibits both GV breakdown (GVBD) and the first polar body (pb1) extrusion in concentration- and time-dependent manners, the most striking result being the very early and narrow temporal window during which denuded primary oocytes released from their follicle are susceptible to a pulse of the drug. This inhibition is bypassed by dithiothreitol (DTT) with an efficiency declining with time, while thiosalicylic acid (TA), an analog of TMS devoid of the mercury atom, has no effect on meiosis reinitiation. These results strongly suggest that the inhibitory effect of TMS is a consequence of its sulfhydryl group oxidising activity. The molecular target(s) of this inhibitory oxidation should however be identified. In contrast to DTT, okadaic acid (OA), known to bypass the inhibitory effect of drugs interfering with protein kinase activities, only induces chromatin condensation and GVBD in TMS-pulsed oocytes with a delay of about 8 hr as compared to the control situation. This confirms that a very early thiol oxidation induced by TMS exerts a much more dramatic effect on resumption on meiosis than any pharmacological manipulation of protein kinase activities leading to activation of MPF.

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Calcium oscillations in human oocytes

Cited by 14 publications

References 17 publications

The Role of X/Y Linker Region and N-terminal EF-hand Domain in Nuclear Translocation and Ca2+ Oscillation-inducing Activities of Phospholipase Cζ, a Mammalian Egg-activating Factor

The Role of X/Y Linker Region and N-terminal EF-hand Domain in Nuclear Translocation and Ca2+ Oscillation-inducing Activities of Phospholipase Cζ, a Mammalian Egg-activating Factor

Recombinant Phospholipase Cζ Has High Ca2+ Sensitivity and Induces Ca2+ Oscillations in Mouse Eggs

The thiol reagent, thimerosal, irreversibly inhibits meiosis reinitiation in mouse oocyte when applied during a very early and narrow temporal window: A pharmacological analysis

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