Journal Article

Reduced amounts and abnormal forms of phospholipase C zeta (PLCζ) in spermatozoa from infertile men

E. Heytens, J. Parrington, K. Coward, C. Young, S. Lambrecht, S.-Y. Yoon, R.A. Fissore, R. Hamer, C.M. Deane, M. Ruas, P. Grasa, R. Soleimani, C.A. Cuvelier, J. Gerris, M. Dhont, D. Deforce, L. Leybaert and P. De Sutter

in Human Reproduction

Published on behalf of European Society of Human Reproduction and Embryology

Volume 24, issue 10, pages 2417-2428
Published in print October 2009 | ISSN: 0268-1161
Published online July 2009 | e-ISSN: 1460-2350 | DOI: https://dx.doi.org/10.1093/humrep/dep207
Reduced amounts and abnormal forms of phospholipase C zeta (PLCζ) in spermatozoa from infertile men

More Like This

Show all results sharing this subject:

  • Reproductive Medicine

GO

Show Summary Details

Preview

BACKGROUND

In mammals, oocyte activation at fertilization is thought to be induced by the sperm-specific phospholipase C zeta (PLCζ). However, it still remains to be conclusively shown that PLCζ is the endogenous agent of oocyte activation. Some types of human infertility appear to be caused by failure of the sperm to activate and this may be due to specific defects in PLCζ.

METHODS AND RESULTS

Immunofluorescence studies showed PLCζ to be localized in the equatorial region of sperm from fertile men, but sperm deficient in oocyte activation exhibited no specific signal in this same region. Immunoblot analysis revealed reduced amounts of PLCζ in sperm from infertile men, and in some cases, the presence of an abnormally low molecular weight form of PLCζ. In one non-globozoospermic case, DNA analysis identified a point mutation in the PLCζ gene that leads to a significant amino acid change in the catalytic region of the protein. Structural modelling suggested that this defect may have important effects upon the structure and function of the PLCζ protein. cRNA corresponding to mutant PLCζ failed to induce calcium oscillations when microinjected into mouse oocytes. Injection of infertile human sperm into mouse oocytes failed to activate the oocyte or trigger calcium oscillations. Injection of such infertile sperm followed by two calcium pulses, induced by assisted oocyte activation, activated the oocytes without inducing the typical pattern of calcium oscillations.

CONCLUSIONS

Our findings illustrate the importance of PLCζ during fertilization and suggest that mutant forms of PLCζ may underlie certain types of human male infertility.

Keywords: PLCζ; infertility; sperm; globozoospermia; oocyte activation

Journal Article.  7599 words.  Illustrated.

Subjects: Reproductive Medicine

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content. subscribe or purchase to access all content.