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Biology of Reproduction 61, 247-252 (1999)
©Copyright 1999 Society for the Study of Reproduction, Inc.

Articles

Hyperactivation of Hamster Sperm Motility by Temperature-Dependent Tyrosine Phosphorylation of an 80-kDa Protein1

Yuming Si2,a

a Department of Biology, College of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153, Japan


   ABSTRACT
TOP
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
Protein phosphorylation and dephosphorylation are believed to play key roles in regulation of sperm motility. Here we examine the effect of temperature on hamster sperm motility and protein tyrosine phosphorylation status. As in previous work, a decrease from 37°C to 22°C caused loss of hyperactivated motility. We now find that cooling also produces a dephosphorylation of several 48–80-kDa flagellar peptides. A return to 37°C restored hyperactivation but resulted in rephosphorylation of only an 80-kDa protein. Conversely, hyperactivation and phosphorylation of the 80-kDa component were insensitive to incubation temperature for sperm incubated with the protein phosphatase inhibitor, calyculin A, or for sperm demembranated by detergent extraction. These results strongly indicate that the temperature-sensitive tyrosine phosphorylation status of an 80-kDa sperm flagellar peptide explains the sensitivity of hyperactivation to temperature.


   INTRODUCTION
TOP
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
The motility of mammalian sperm undergoes two alterations between mating and fertilization. The first occurs at ejaculation when the motility of sperm from the cauda epididymides is initiated. After several hours in the female reproductive tract, sperm show a frantic flagellar movement [1] called hyperactivation [2]. Hyperactivation is believed to enable the sperm to generate adequate force to liberate themselves from the oviductal isthmus and to potentiate sperm movement through the cumulus matrix, or zona pellucida, of the oocyte [3, 4]. Hyperactivation can also be induced in vitro by incubating sperm under a medium supporting capacitation. In vitro studies have identified a number of physiological factors necessary for sperm hyperactivation including Ca2+, HCO3-, K+, BSA, and metabolic substrates [3, 5]. However, the intracellular biochemical mechanisms underlying the regulation of sperm hyperactivation remain largely undefined.

Protein tyrosine phosphorylation is an important posttranslational event involved in diverse biological processes [6]. Increasing evidence indicates that protein tyrosine phosphorylation is associated with sperm motility activation, hyperactivation, capacitation, and fertilization [7–11]. However, relatively little is known about the interrelationship between protein tyrosine phosphorylation status and sperm functions. It has been shown previously that temperature reversibly regulates the initiation and maintenance of hamster sperm hyperactivation: the loss and acquisition of hyperactivated motility could be repeated many times as temperature was lowered and increased between 37°C and 22°C [12].

In the accompanying paper, tyrosine phosphorylation of sperm flagellar proteins is shown to be involved in sperm motility hyperactivation [8]. However, we do not know whether the loss of sperm hyperactivation in low temperature is associated with protein dephosphorylation. It must be appreciated that if protein phosphorylation is essential for sperm hyperactivation, dephosphorylation/rephosphorylation of some motility-related phosphorylated protein(s) may block/restore hyperactivation. The present study was designed to investigate whether the temperature-dependent loss and acquisition of sperm hyperactivation are associated with protein tyrosine dephosphorylation and rephosphorylation.


   MATERIALS AND METHODS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
Reagents and Culture Medium

Anti-phosphotyrosine monoclonal antibody (Clone PY20) was obtained from Transduction Laboratories (Lexington, KY). Horseradish peroxidase-conjugated goat anti-mouse IgG was from Bio Source International (Camarillo, CA). Fraction V BSA was from Calbiochem Corporation (cat. #126591; La Jolla, CA). Glass beads (<= 106 µm) were from Sigma Chemical Company (St. Louis, MO). Other chemicals were of reagent grade from Wako Pure Chemical Industries, Ltd. (Osaka, Japan). Stock solution of calyculin A was prepared in dimethyl sulfoxide and stored at -20°C. Control without calyculin A received an equivalent amount of dimethyl sulfoxide. Modified Tyrode's albumin lactate pyruvate (TALP) medium [13] was used throughout these experiments. The preparation of the medium was previously described [12].

Quantitative Analysis of Sperm Movement

Methods for examination and recording of sperm movement were described previously by Si [12]. The sperm motility parameters analyzed in this study were straight-line velocity (VSL), curvilinear velocity (VCL), flagellar beat frequency, and principal bend and reverse bend angles.

Flagellar Preparation

Approximately 50 µl of epididymal sperm mass was collected from golden hamster [8] and placed at the bottom of a 100-ml beaker, then gently covered with 100 ml of modified TALP medium and incubated at 37°C under 5% CO2 in air. There were two parallel experiments to prepare sperm flagella. First, in the presence of calyculin A, sperm were incubated for 70 min at 37°C under 5% CO2 in air to allow hyperactivation to occur; then 30 ml of sperm "swim-up fraction" was collected and divided into three 10-ml aliquots. One aliquot was immediately demembranated by adding 10 µl of 10% Triton X-100; another aliquot was kept at room temperature of 22°C for 30 min prior to demembranation. The remainder was also kept at 22°C for 30 min and then reequilibrated at 37°C for an additional 30 min followed by demembranation. Second, control sperm without calyculin A treatment were incubated for 3 h to allow hyperactivation to occur, and then 30 ml of sperm swim-up fraction was collected, divided into three 10-ml aliquots, and either demembranated immediately or subjected to the same temperature changes as the calyculin A-treated sperm before demembranation. The isolation of pure flagella from the demembranated sperm using glass beads and centrifugation is described in the accompanying paper [8].

SDS-PAGE and Western Blotting

Isolated sperm flagella (~6 x 105 cells) were solubilized in Laemmli sample buffer and run on 8% gels for electrophoresis [14]. The proteins were electroblotted to a polyvinylidene difluoride membrane (Millipore Corp., Bedford, MA) according to the method of Towbin et al. [15]. Nonspecific binding sites on the membrane were blocked for 1 h with 5% BSA in Tris-buffered saline (TTBS; 150 mM NaCl, 20 mM Tris-HCl, 0.1% Tween 20, pH 7.6). Immunoblots were incubated for 1 h with monoclonal anti-phosphotyrosine antibody PY20 (1 µg/ml in TTBS). After three washes (10 min each with TTBS), the blots were incubated with horseradish peroxidase-conjugated goat anti-mouse IgG at 1:1000 dilution. After 1-h incubation, the membrane was washed three times (20 min each with TTBS), and the peroxidase activity was detected using 4-chloro-1-naphtol as a substrate [16]. The reaction was stopped by washing in double-distilled water. Secondary antibody alone was used as a control.


   RESULTS
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 REFERENCES
 
Loss and Reacquisition of Hyperactivated Movement in Membrane-Intact Sperm Were Associated with Protein Tyrosine Dephosphorylation and Rephosphorylation

Hamster sperm were hyperactivated during incubation in modified TALP medium for 3.5 h at 37°C. A previous study [12] showed that the motility of such sperm is different when examined at 37°C as compared to 22°C. At 37°C, a hyperactivated movement with large principal bend and reverse bend is observed. At 22°C, hyperactivated motility is lost. Strikingly, the reverse bend that originates in the middle piece does not propagate to the principal piece of the flagellum.

Anti-phosphotyrosine immunoblot analysis of sperm hyperactivated at 37°C detected four flagellar peptides migrating at 90, 80, 62, and 48 kDa (Fig. 1, lane A). Immunoblot analysis of extracts from sperm incubated for 30 min at 22°C showed only a 90-kDa component (Fig. 1, lane B). When sperm were reequilibrated at 37°C for 30 min, they regained hyperactivation, but only the 80-kDa component was rephosphorylated in these restored cells (Fig. 1, lane C). These results provide evidence that temperature-dependent regulation of sperm hyperactivation is tightly correlated with tyrosine phosphorylation/dephosphorylation of an 80-kDa flagellar protein.



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  		FIG. 1. Effect of temperature on protein tyrosine phosphorylation in membrane-intact hamster sperm. Three 10-ml aliquots of hyperactivated sperm were taken. The first was immediately demembranated at 37°C (lane A), the second kept at 22°C for 30 min before demembranation (lane B), and the third kept at 22°C for 30 min and then reequilibrated at 37°C for 30 min followed by demembranation (lane C). Equal numbers of flagella were solubilized for SDS-PAGE and immunoblotting with anti-phosphotyrosine antibody. Molecular weight standards (x 10-3) are indicated to the left.

Temperature-Independent Protein Tyrosine Phosphorylation and Hyperactivation in Calyculin A-Treated Sperm

As demonstrated in the accompanying paper, incubation of sperm with calyculin A greatly accelerated the onset of sperm hyperactivation [8]. After 70 min of incubation in the presence of 2 µM calyculin A, sperm flagellum displayed a normal hyperactivated waveform at 37°C (Fig. 2A). Immunoblot analysis showed that only the 80-kDa protein was tyrosine phosphorylated (Fig. 3, lane A). Surprisingly, when the temperature was lowered to 22°C from 37°C, unlike the control sperm [12], the calyculin A-treated sperm showed a decrease in the beat frequency, VSL, and VCL (Fig. 4) but no change in flagellar bending pattern (Fig. 2B). Quantitative analysis of flagellar bend angles revealed that the large principal bend (the bend in the direction of the curvature of the head) and reverse bend angles through the whole flagella remained almost unchanged (Fig. 5). These sperm were able to retain their large-amplitude flagellar bending and erratic swimming trajectories for over 1 h at 22°C. Moreover, under the 22°C condition, the 80-kDa protein of the calyculin A-treated sperm still remained tyrosine phosphorylated (Fig. 3, lane B). When the temperature was restored to 37°C, sperm flagellar movement became more vigorous (Fig. 4), and tyrosine phosphorylation of the 80-kDa protein was unaltered (Fig. 3, lane C). These results suggest that tyrosine phosphorylation of the 80-kDa protein appears to be critical for maintenance of hyperactivated motility.



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  		FIG. 2. A comparison of flagellar waveforms of calyculin A-induced-hyperactivated sperm at 37°C (A) and 22°C (B). Pictures from videotapes. Bar = 25 µm.



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  		FIG. 3. Effect of temperature on protein tyrosine phosphorylation in calyculin A-induced-hyperactivated hamster sperm. Three 10-ml aliquots of calyculin A-induced- hyperactivated sperm were taken. The first was immediately demembranated at 37°C (lane A), the second kept at 22°C for 30 min before demembranation (lane B), and the third kept at 22°C for 30 min and then reequilibrated at 37°C for 30 min followed by demembranation (lane C). Equal numbers of flagella were solubilized for SDS-PAGE and immunoblotting with anti-phosphotyrosine antibody. Molecular weight standards (x 10-3) are indicated to the left.



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  		FIG. 4. Effects of temperature on calyculin A-induced-hyperactivated sperm motility. Sperm motility was measured at 37°C, 33°C, or 22°C at 5-min intervals. After 30 min of incubation at 22°C, motility was measured at 22°C, 33°C, or 37°C at 5-min intervals. Each bar represents the mean ± SD (n >= 8).



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  		FIG. 5. Changes in angles of principal bends (A) and reverse bends (B) of the flagella of calyculin A-induced-hyperactivated sperm. The abscissa represents the curvilinear distance from head-midpiece junction to the bend center along the flagella [12]. Solid circles, 22°C; open circles, 37°C. Each point represents the mean ± SD (n >= 8).

Temperature-Independent Protein Tyrosine Phosphorylation and Hyperactivation in Demembranated Sperm

Membrane-intact hyperactivated sperm absolutely require body temperature of 37°C to display hyperactivated movement, but demembranated sperm exhibit a hyperactivation-like movement independent of temperature fluctuation between 22°C and 37°C [12]. This observation indicates that, unlike the situation in fowl sperm [17], hamster sperm plasma membrane could be involved in the regulation of sperm hyperactivation. To gain further insight into the role of plasma membrane in sperm hyperactivation, we repeated the temperature and protein tyrosine phosphorylation experiments using demembranated sperm.

Hyperactivated sperm were demembranated at 37°C with Triton X-100. Demembranated sperm flagella were either solubilized immediately in SDS buffer or kept at 22°C for 30 min prior to solubilization in SDS buffer. Immunoblot analysis revealed no significant differences in protein tyrosine phosphorylation between the flagellar extracts taken at 37°C and 22°C (Fig. 6, lanes A and B). This finding indicates that the tyrosine-phosphorylated proteins in hyperactivated sperm at 37°C did not undergo dephosphorylation at 22°C when the plasma membrane was removed. This result is consistent with the observation that the demembranated sperm exhibit hyperactivation at either 37°C or 22°C [12], and clearly demonstrates a strong correlation between protein tyrosine phosphorylation and sperm hyperactivation.



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  		FIG. 6. Effect of temperature on tyrosine phosphorylation in hyperactivated, demembranated hamster sperm. Two 10-ml aliquots were taken and immediately demembranated at 37°C. The first was immediately subjected to flagellar isolation, then solubilized in SDS buffer (lane A). The second was kept at 22°C for 30 min; then sperm flagella were isolated and solubilized in SDS buffer (lane B). The lanes are Western blots with anti-phosphotyrosine antibody. Molecular weight standards (x 10-3) are indicated to the left.


   DISCUSSION
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
REFERENCES
 
We investigated the relationship between temperature and protein tyrosine phosphorylation in hyperactivated sperm flagella. We demonstrate that 1) tyrosine dephosphorylation/rephosphorylation of an 80-kDa protein is tightly correlated with temperature-dependent loss/reacquisition of sperm hyperactivation; 2) in the presence of calyculin A, the 80-kDa protein tyrosine phosphorylation and sperm hyperactivation are temperature independent; and 3) in the demembranated sperm, protein tyrosine dephosphorylation does not occur even at the low temperature of 22°C.

Temperature-dependent regulation of sperm motility is also reported in fowl sperm. However, unlike hyperactivated hamster sperm, ejaculated fowl sperm are immotile at the normal avian body temperature of 40°C, but motility is initiated by adding Ca2+ or lowing temperature to 30°C [17]. Moreover, demembranated, ATP-reactivated sperm are also immotile at 40°C, but motile at 30°C, suggesting that temperature acts directly on the motor apparatus of fowl sperm flagella. Conversely, in the hamster, since demembranated sperm display a hyperactivation-like motility independent of temperature changes, the plasma membrane appears to be involved in the temperature-dependent regulation of sperm hyperactivation [12], although an intracellular component also could be critical.

It is known that, in ram sperm plasma membrane, temperature change between the scrotal temperature of 35°C and body temperature of 38°C causes some thermotropic lipid phase transitions from a liquid-crystalline to a gel state, or vice versa [18]; in bovine sperm, temperature also affects lipid diffusion in the plasma membrane [19]. Such changes in membrane lipid diffusibility have been shown to be associated with sperm hyperactivation and capacitation [20, 21]. In addition, temperature alteration also modifies antigen sites on sperm plasma membrane. Incubation of guinea pig sperm at 37°C under a capacitating medium causes an antigen migration to the middle piece region from the principal piece and end piece, while at 33°C, almost no sperm show migration of the antigen to the middle piece [22]. Together, modifications in membrane composition and structure by temperature can lead to alterations in membrane permeability and membrane-bound enzyme activity [18, 23]. The biological consequences of such alteration in membrane permeability could be changes in intracellular concentration of Ca2+ and/or HCO3- [24, 25]. The roles of Ca2+ and HCO3- in the control of sperm hyperactivation have been firmly established, and therefore temperature may owe its effect to regulating sperm hyperactivation and protein tyrosine phosphorylation through Ca2+ and/or HCO3- signaling pathways [9, 10, 26–31]. Alternatively, since most protein tyrosine kinases (PTKs) are associated with the plasma membrane, temperature-induced modification of membrane properties could directly result in regulation of sperm membrane-bound PTK activity [6].

There is substantial evidence for a role of protein phosphatases in regulating sperm motility [32]. Addition of exogenous protein phosphatase inhibited demembranated ATP-reactivated sperm movement and protein phosphorylation [33, 34]; treatment of immotile demembranated fowl sperm with protein phosphatase inhibitor, calyculin A, induced reactivated motility [35]. Additionally, calyculin A was also capable of initiating immotile bovine caput epididymal sperm motility without affecting intracellular levels of cAMP, pH, and Ca2+ [36] and of stimulating activated primate sperm motility [37, 38] as well as capacitation [39]. These observations suggest that 1) calyculin A-sensitive protein phosphatases are present in sperm and involved in regulation of sperm functions; 2) cAMP-dependent protein phosphorylation is dependent on the balance of activities of PKA and protein phosphatases. The present study demonstrates that calyculin A can overcome the low temperature-dependent inhibition of sperm hyperactivation and protein tyrosine phosphorylation. One interpretation of this information could be that, under low-temperature conditions, the intracellular concentration of cAMP may decrease, but target protein phosphorylation remains unaltered because of the inhibition of protein phosphatase by calyculin A. The target protein could be a motility-related peptide responsible for hyperactivated motility or/and sperm PTK per se needed for phosphorylation of substrate, e.g., the 80-kDa protein.

Tyrosine phosphorylation, dephosphorylation, and rephosphorylation of the 80-kDa protein in hamster sperm flagella are tightly associated with the acquisition, loss, and reacquisition of sperm hyperactivation. The 80-kDa protein was localized to the flagellar principal piece by indirect immunofluorescence, suggesting that this protein is a fibrous sheath (FS) component [8]. With regard to the 80-kDa protein, biochemical studies show that the rat sperm FS is composed predominantly of a single polypeptide of 80 kDa [40]; the major FS polypeptide of mouse sperm is an 82-kDa protein [41]. The 82-kDa protein has recently been identified as an A-kinase anchoring protein (AKAP) and named AKAP82 [41, 42]. In human sperm, one prominent phosphotyrosine-containing protein of 82 kDa is the human homologue of mouse sperm AKAP82, and the increase in the tyrosine phosphorylation of AKAP82 is correlated with human sperm capacitation [42]. Thus, the approximately 80-kDa protein appears to be a common polypeptide of mammalian sperm FS, and its tyrosine phosphorylation seems necessary for sperm hyperactivation as well as capacitation.


   ACKNOWLEDGMENTS
 
The author greatly appreciates the use of Dr. Makoto Okuno's equipment and facilities.


   FOOTNOTES
 
1 This work was supported by research grants P-95118 and 07–95118 from the Japan Society for the Promotion of Science. Back

2 Correspondence: Yuming Si, Department of Anatomy and Cell Biology, Temple University School of Medicine, 3400 North Broad Street, Philadelphia, PA 19140. FAX: 215 707 2966; ysi{at}nimbus.temple.edu Back

Accepted: February 25, 1999.

Received: November 17, 1998.


   REFERENCES
TOP
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 

  1. Yanagimachi R. The movement of golden hamster spermatozoa before and after capacitation. J Reprod Fertil 1970; 23:193–196.[Abstract/Free Full Text]
  2. Yanagimachi R. Mechanisms of fertilization in mammals. In: Mastroianni L, Biggers JD (eds.), Fertilization and Embryonic Development in Vitro. New York: Plenum Press; 1981: 81–182.
  3. Yanagimachi R. Mammalian fertilization. In: Knobil E, Neill JD (eds.), The Physiology of Reproduction. New York: Raven Press Ltd.; 1994: 189–317.
  4. Suarez SS. Hyperactivated motility in sperm. J Androl 1996; 17:331–335.[Abstract/Free Full Text]
  5. Si Y. Hyperactivated motility of mammalian sperm. Mol Androl 1996; 8:235–249.
  6. Hunter T, Cooper JA. Protein-tyrosine kinase. Annu Rev Biochem 1985; 54:897–930.[Medline]
  7. Hayashi H, Yamamoto K, Yonekawa H, Morisawa M. Involvement of tyrosine protein kinase in the initiation of flagellar movement in rainbow trout spermatozoa. J Biol Chemm 1987; 262:16692–16698.
  8. Si Y, Okuno M. Role of tyrosine phosphorylation of flagellar proteins in hamster sperm hyperactivation. Biol Reprod 1999; 61:240–246.[Abstract/Free Full Text]
  9. Visconti PE, Bailey JL, Moore GD, Pan D, Olds-Clarke P, Kopf GS. Capacitation of mouse spermatozoa. I. Correlation between the capacitation and protein tyrosine phosphorylation. Development 1995; 121:1129–1137.[Abstract]
  10. Visconti PE, Moore GD, Bailey JL, Leclerc P, Connors SA, Pan D, Olds-Clarke P, Kopf GS. Capacitation of mouse spermatozoa. II. Protein tyrosine phosphorylation and capacitation are regulated by a cAMP-dependent pathway. Development 1995; 121:1139–1150.[Abstract]
  11. Burks DJ, Carballada R, Moore HDM, Saling PM. Interaction of a tyrosine kinase from human sperm with the zona pellucida at fertilization. Science 1995; 269:83–86.[Abstract/Free Full Text]
  12. Si Y. Temperature-dependent hyperactivated movement of hamster spermatozoa. Biol Reprod 1997; 57:1407–1412.[Abstract]
  13. Maleszewski M, Kline D, Yanagimachi R. Activation of hamster zona-free oocytes by homologous and heterologous spermatozoa. J Reprod Fertil 1995; 105:99–107.[Abstract/Free Full Text]
  14. Laemmli UK. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature 1970; 227:680–685.[CrossRef][Medline]
  15. Towbin H, Staehelin TH, Gordon J. Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications. Proc Natl Acad Sci USA 1979; 76:4358–4364.
  16. King SM, Otter T, Witman GB. Characterization of monoclonal antibodies against Chlamydomonas flagellar dynein by high-resolution protein blotting. Proc Natl Acad Sci USA 1985; 82:4717–4721.[Abstract/Free Full Text]
  17. Ashizawa K, Maeda S, Okauchi K. The mechanisms of reversible immobilization of fowl spermatozoa at body temperature. J Reprod Fertil 1989; 86:263–270.[Abstract/Free Full Text]
  18. Holt WV, North RD. Thermotropic phase transitions in the plasma membrane of spermatozoa. J Reprod Fertil 1986; 78:447–457.[Abstract/Free Full Text]
  19. Ladha S, James PS, Clark DC, Howes EA, Jones R. Lateral mobility of plasma membrane lipids in bull spermatozoa: heterogeneity between surface domains and rigidification following cell death. J Cell Sci 1997; 110:1041–1050.[Abstract]
  20. Wolf DE, Hagopian SS, Ishijima S. Changes in sperm plasma membrane lipid diffusibility after hyperactivation during in vitro capacitation in the mouse. J Cell Biol 1986; 102:1372–1377.[Abstract/Free Full Text]
  21. Wolf DE, Cardullo RA. Physiological properties of the mammalian sperm plasma membrane. In: Baccetti B (ed.), Comparative Spermatology 20 Years After. New York: Raven Press Ltd.; 1991: 599–604.
  22. Myles DG, Primakoff P. Localized surface antigens of guinea pig sperm migrate to new regions prior to fertilization. J Cell Biol 1984; 99:1634–1641.[Abstract/Free Full Text]
  23. Tocanne JF, Dupou-Cezanne L, Lopez A, Tournier JF. Lipid lateral diffusion and membrane organization. FEBS Lett 1989; 257:10–16.[CrossRef][Medline]
  24. Babcock DF, Singh JP, Lardy H. Alteration of membrane permeability to calcium ions during maturation of bovine spermatozoa. Dev Biol 1979; 69:85–93.[CrossRef][Medline]
  25. Okamura N, Tajima Y, Sugita Y. Decrease in bicarbonate transport activities during epididymal maturation of porcine sperm. Biochem Biophys Res Commun 1988; 157:1280–1287.[CrossRef][Medline]
  26. Yanagimachi R, Usui N. Calcium dependence of the acrosome reaction and activation of guinea pig spermatozoa. Exp Cell Res 1974; 89:161–174.[CrossRef][Medline]
  27. Yanagimachi R. Requirement of extracellular calcium ions for various stages of fertilization and fertilization-related phenomena in the hamster. Gamete Res 1982; 5:323–344.[CrossRef]
  28. Neill J, Olds-Clarke P. A computer-assisted assay for mouse sperm hyperactivation demonstrates that bicarbonate but not bovine serum albumin is required. Gamete Res 1987; 18:121–140.[CrossRef][Medline]
  29. Boatman DE, Robbins RS. Bicarbonate:carbon-dioxide regulation of sperm capacitation, hyperactivated motility, and acrosome reaction. Biol Reprod 1991; 44:806–813.[Abstract]
  30. Suarez SS, Varosi SM, Dai XB. Intracellular calcium increases with hyperactivation in intact, moving hamster sperm and oscillates with the flagellar beat cycle. Proc Natl Acad Sci USA 1993; 90:4600–4664.
  31. Stauss C, Votta TJ, Suarez SS. Sperm motility hyperactivation facilitates penetration of the hamster zona pellucida. Biol Reprod 1995; 53:1280–1285.[Abstract]
  32. Tash JS, Bracho GE. Regulation of sperm motility: emerging evidence for a major roles for protein phosphatases. J Androl 1994; 15:505–509.[Free Full Text]
  33. Takahashi D, Murofushi H, Ishiguro K, Ikeda L, Sakai H. Phosphoprotein phosphatase inhibits flagellar movement of Triton models of sea urchin spermatozoa. Cell Struct Funct 1985; 10:327–337.[Medline]
  34. Ashizawa K, Hashimoto K, Tsuzuki Y. Regulation of fowl sperm flagellar motility by protein phosphatase type 1 and its relationship with dephosphorylation of axonemal and/or accessory cytoskeletal proteins. Biochem Biophys Res Commun 1997; 235:108–112.[CrossRef][Medline]
  35. Ashizawa K, Wishart GJ, Tomonaga H, Nishinakama K, Tsuzuki Y. Presence of protein phosphatase type 1 and its involvement in temperature-dependent flagellar movement of fowl spermatozoa. FEBS Lett 1994; 350:130–134.[CrossRef][Medline]
  36. Vijayaraghavan S, Stephens DT, Trautman K, Smith GD, Khatra B, Greengard P. Sperm motility development in the epididymis is associated with decreased glycogen synthase kinase-3 and protein phosphatase 1 activity. Biol Reprod 1996; 54:709–718.[Abstract]
  37. Leclerc P, De-Lamirande E, Gagnon C. Cyclic adenosine 3',5' monophosphate-dependent regulation of protein tyrosine phosphorylation in relation to human sperm capacitation and motility. Biol Reprod 1996; 55:684–692.[Abstract]
  38. Smith GD, Wolf DP, Trautman KC, da Cruz e Silva EF, Greengard P, Vijayaraghavan S. Primate sperm contain protein phosphatase 1, a biochemical mediator of motility. Biol Reprod 1996; 54:719–727.[Abstract]
  39. Furuya S, Endo Y, Osumi K, Oba M, Nozawa S, Suzuki S. Calyculin A, a protein phosphatase inhibitor, enhances capacitation of human sperm. Fertil Steril 1993; 59:216–222.[Medline]
  40. Olson GE, Hamilton DW, Fawcett DW. Isolation and characterization of the fibrous sheath of rat epididymal spermatozoa. Biol Reprod 1976; 14:517–530.[Abstract]
  41. Carrera A, Gerton G, Moss SB. The major fibrous sheath polypeptide of mouse sperm: structural and functional similarities to the A-kinase anchoring proteins. Dev Biol 1994; 165:272–284.[CrossRef][Medline]
  42. Carrera A, Moos J, Ning XP, Gerton G, Tesarik J, Kopf GS, Moss SB. Regulation of protein tyrosine phosphorylation in human sperm by a calcium/calmodulin-dependent mechanism: identification of A kinase anchor proteins as major substrates for tyrosine phosphorylation. Dev Biol 1996; 180:284–296.[CrossRef][Medline]



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