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Whole-cell patch-clamp measurements of spermatozoa reveal an alkaline-activated Ca2+ channel

Abstract

In mammals, sperm cells become motile during ejaculation and swim up the female reproductive tract. Before fertilization and to overcome various barriers, their motility must be hyperactivated, a motion that is characterized by vigorous asymmetric tail beating1. Hyperactivation requires an increase in calcium in the flagella, a process that probably involves plasmalemmal ion channels2,3,4,5,6,7,8. Numerous attempts in the past two decades to understand sperm cell channels have been frustrated by the difficulty of measuring spermatozoan transmembrane ion currents2,3,9,10,11,12,13,14,15,16. Here, by using a simple approach to patch-clamp spermatozoa and to characterize whole-spermatozoan currents, we describe a constitutively active flagellar calcium channel that is strongly potentiated by intracellular alkalinization. This current is not present in spermatozoa lacking the sperm-specific putative ion channel protein, CatSper1. This plasma membrane protein of the six transmembrane-spanning ion channel superfamily is specifically localized to the principal piece of the sperm tail and is required for sperm cell hyperactivation and male fertility4,5. Our results identify CatSper1 as a component of the key flagellar calcium channel, and suggest that intracellular alkalinization potentiates CatSper current to increase intraflagellar calcium and induce sperm hyperactivation.

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Figure 1: Whole-cell patch-clamp recordings from intact spermatozoa.
Figure 2: I CatSper originates from the principal piece of the sperm cell flagellum.
Figure 3: I CatSper is Ca 2+ selective.
Figure 4: pH and voltage-dependence of ICatSper.

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References

  1. Ho, H. C. & Suarez, S. S. Hyperactivation of mammalian spermatozoa: function and regulation. Reproduction 122, 519–526 (2001)

    Article  CAS  Google Scholar 

  2. Darszon, A., Labarca, P., Nishigaki, T. & Espinosa, F. Ion channels in sperm physiology. Physiol. Rev. 79, 481–510 (1999)

    Article  CAS  Google Scholar 

  3. Darszon, A. et al. Calcium channels and Ca2+ fluctuations in sperm physiology. Int. Rev. Cytol. 243, 79–172 (2005)

    Article  CAS  Google Scholar 

  4. Ren, D. et al. A sperm ion channel required for sperm motility and male fertility. Nature 413, 603–609 (2001)

    Article  ADS  CAS  Google Scholar 

  5. Carlson, A. E. et al. CatSper1 required for evoked Ca2+ entry and control of flagellar function in sperm. Proc. Natl Acad. Sci. USA 100, 14864–14868 (2003)

    Article  ADS  CAS  Google Scholar 

  6. Carlson, A. E. et al. Identical phenotypes of CatSper1 and CatSper2 null sperm. J. Biol. Chem. 280, 32238–32244 (2005)

    Article  CAS  Google Scholar 

  7. Quill, T. A., Ren, D., Clapham, D. E. & Garbers, D. L. A voltage-gated ion channel expressed specifically in spermatozoa. Proc. Natl Acad. Sci. USA 98, 12527–12531 (2001)

    Article  ADS  CAS  Google Scholar 

  8. Quill, T. A. et al. Hyperactivated sperm motility driven by CatSper2 is required for fertilization. Proc. Natl Acad. Sci. USA 100, 14869–14874 (2003)

    Article  ADS  CAS  Google Scholar 

  9. Babcock, D. F., Bosma, M. M., Battaglia, D. E. & Darszon, A. Early persistent activation of sperm K+ channels by the egg peptide speract. Proc. Natl Acad. Sci. USA 89, 6001–6005 (1992)

    Article  ADS  CAS  Google Scholar 

  10. Espinosa, F. et al. Mouse sperm patch-clamp recordings reveal single Cl- channels sensitive to niflumic acid, a blocker of the sperm acrosome reaction. FEBS Lett. 426, 47–51 (1998)

    Article  CAS  Google Scholar 

  11. Gu, Y., Kirkman-Brown, J. C., Korchev, Y., Barratt, C. L. & Publicover, S. J. Multi-state, 4-aminopyridine-sensitive ion channels in human spermatozoa. Dev. Biol. 274, 308–317 (2004)

    Article  CAS  Google Scholar 

  12. Guerrero, A., Sanchez, J. A. & Darszon, A. Single-channel activity in sea urchin sperm revealed by the patch-clamp technique. FEBS Lett. 220, 295–298 (1987)

    Article  CAS  Google Scholar 

  13. Sanchez, D., Labarca, P. & Darszon, A. Sea urchin sperm cation-selective channels directly modulated by cAMP. FEBS Lett. 503, 111–115 (2001)

    Article  CAS  Google Scholar 

  14. Gorelik, J. et al. Ion channels in small cells and subcellular structures can be studied with a smart patch-clamp system. Biophys. J. 83, 3296–3303 (2002)

    Article  ADS  CAS  Google Scholar 

  15. Weyand, I. et al. Cloning and functional expression of a cyclic-nucleotide-gated channel from mammalian sperm. Nature 368, 859–863 (1994)

    Article  ADS  CAS  Google Scholar 

  16. Florman, H. M., Arnoult, C., Kazam, I. G., Li, C. & O'Toole, C. M. A perspective on the control of mammalian fertilization by egg-activated ion channels in sperm: a tale of two channels. Biol. Reprod. 59, 12–16 (1998)

    Article  CAS  Google Scholar 

  17. Lobley, A., Pierron, V., Reynolds, L., Allen, L. & Michalovich, D. Identification of human and mouse CatSper3 and CatSper4 genes: characterisation of a common interaction domain and evidence for expression in testis. Reprod. Biol. Endocrinol. 1, 53 (2003)

    Article  Google Scholar 

  18. Cooper, T. G. Cytoplasmic droplets: the good, the bad or just confusing? Hum. Reprod. 20, 9–11 (2005)

    Article  CAS  Google Scholar 

  19. Gonzalez-Martinez, M. T. Induction of a sodium-dependent depolarization by external calcium removal in human sperm. J. Biol. Chem. 278, 36304–36310 (2003)

    Article  CAS  Google Scholar 

  20. Espinosa, F. & Darszon, A. Mouse sperm membrane potential: changes induced by Ca2+. FEBS Lett. 372, 119–125 (1995)

    Article  CAS  Google Scholar 

  21. Horn, R. & Marty, A. Muscarinic activation of ionic currents measured by a new whole-cell recording method. J. Gen. Physiol. 92, 145–159 (1988)

    Article  CAS  Google Scholar 

  22. Hille, B. Ion Channels of Excitable Membranes (Sinauer Associates, Sunderland, MA, 2001)

    Google Scholar 

  23. Sather, W. A. & McCleskey, E. W. Permeation and selectivity in calcium channels. Annu. Rev. Physiol. 65, 133–159 (2003)

    Article  CAS  Google Scholar 

  24. Fraire-Zamora, J. J. & Gonzalez-Martinez, M. T. Effect of intracellular pH on depolarization-evoked calcium influx in human sperm. Am. J. Physiol. Cell. Physiol. 287, C1688–C1696 (2004)

    Article  CAS  Google Scholar 

  25. Santi, C. M., Santos, T., Hernandez-Cruz, A. & Darszon, A. Properties of a novel pH-dependent Ca2+ permeation pathway present in male germ cells with possible roles in spermatogenesis and mature sperm function. J. Gen. Physiol. 112, 33–53 (1998)

    Article  CAS  Google Scholar 

  26. Babcock, D. F. Examination of the intracellular ionic environment and of ionophore action by null point measurements employing the fluorescein chromophore. J. Biol. Chem. 258, 6380–6389 (1983)

    CAS  PubMed  Google Scholar 

  27. Zeng, Y., Oberdorf, J. A. & Florman, H. M. pH regulation in mouse sperm: identification of Na+-, Cl-, and HCO3--dependent and arylaminobenzoate-dependent regulatory mechanisms and characterization of their roles in sperm capacitation. Dev. Biol. 173, 510–520 (1996)

    Article  CAS  Google Scholar 

  28. Ho, H. C., Granish, K. A. & Suarez, S. S. Hyperactivated motility of bull sperm is triggered at the axoneme by Ca2+ and not cAMP. Dev. Biol. 250, 208–217 (2002)

    Article  CAS  Google Scholar 

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Acknowledgements

We thank H. Qi for help in preparation of sperm cells and for discussion.

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Competing interests

D.E.C. has a patent pending on the use of CatSper1 as a contraception target.

Supplementary information

Supplementary Figure 1.

Monovalent ICatSper is potentiated by intracellular alkalinization. (PDF 272 kb)

Supplementary Figure 2.

CatSper conducts inward and outward Ba2+ current in response to a voltage ramp in symmetrical 50 mM [Ba2+]. (PDF 279 kb)

Supplementary Figure 3.

ICatSper is insensitive to cyclic nucleotides. (PDF 676 kb)

Supplementary Movie

Application of the patch pipette to the small cytoplasmic droplet of the sperm, a remnant of the precursor germ cell cytoplasm located on the midpiece of a mature sperm cell that is shed around the time of ejaculation. (AVI 7515 kb)

Supplementary Legends

Legends to accompany the above Supplementary Figures and Supplementary Movie. (DOC 26 kb)

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Kirichok, Y., Navarro, B. & Clapham, D. Whole-cell patch-clamp measurements of spermatozoa reveal an alkaline-activated Ca2+ channel. Nature 439, 737–740 (2006). https://doi.org/10.1038/nature04417

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