Mol. Hum. Reprod. Advance Access originally published online on June 26, 2007
Molecular Human Reproduction 2007 13(9):605-613; doi:10.1093/molehr/gam043
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Analysis of chaperone proteins associated with human spermatozoa during capacitation
1Reproductive Science Group, Discipline of Biological Sciences, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia 2ARC Centre of Excellence in Biotechnology and Development, Discipline of Biological Sciences, School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
3 Correspondence address. Tel: +61 2 4921 2082; Fax: +61 2 9216 308; E-mail: john.aitken{at}newcastle.edu.au
Mammalian spermatozoa must undergo a post-ejaculatory period of maturation, known as capacitation, before they can engage in the process of fertilization. Studies in the mouse have established that capacitation facilitates sperm–zona recognition via mechanisms that involve the appearance of tyrosine phosphorylated chaperone proteins on the sperm surface overlying the acrosome, the site of sperm–zona recognition. In this study, we examined whether a similar relationship existed between the tyrosine phosphorylation events associated with capacitation and sperm–zona interaction in human spermatozoa. These studies confirmed that capacitation is associated with an increase in both sperm–zona binding and an increase in tyrosine phosphorylation over the sperm tail. However, we could not detect the surface expression of phosphotyrosine residues over the sperm head, as observed with murine spermatozoa. Moreover, although we could clearly detect a number of chaperone proteins in human spermatozoa including HSPE1, DNAJB1, HSPD1, HSPA1A, HSPCA, HSPH1, HSPA5 and TRA1, none of these molecules were expressed on the sperm surface. On the basis of these results, it is unlikely that these proteins play an active role in the remodeling of the sperm surface during capacitation. We conclude that strong species-specific differences exist in the molecular mechanisms that drive sperm–egg recognition and that alternative, chaperone-independent, mechanisms must underpin sperm–zona interaction in the human.
Key words: spermatozoa/capacitation/chaperone/zona pellucida
Submitted on April 18, 2007; accepted on May 14, 2007.
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  D. C Wilkerson and K. D Sarge RNA polymerase II interacts with the Hspa1b promoter in mouse epididymal spermatozoa Reproduction, June 1, 2009; 137(6): 923 - 929. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. M A Elliott, R. E Lloyd, A. Fazeli, E. Sostaric, A S. Georgiou, N. Satake, P. F Watson, and W. V Holt Effects of HSPA8, an evolutionarily conserved oviductal protein, on boar and bull spermatozoa Reproduction, February 1, 2009; 137(2): 191 - 203. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Varano, A. Lombardi, G. Cantini, G. Forti, E. Baldi, and M. Luconi Src activation triggers capacitation and acrosome reaction but not motility in human spermatozoa Hum. Reprod., December 1, 2008; 23(12): 2652 - 2662. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Jones, P. S. James, D. Oxley, J. Coadwell, F. Suzuki-Toyota, and E. A. Howes The Equatorial Subsegment in Mammalian Spermatozoa Is Enriched in Tyrosine Phosphorylated Proteins Biol Reprod, September 1, 2008; 79(3): 421 - 431. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. A. Mitchell, B. Nixon, M. A. Baker, and R. J. Aitken Investigation of the role of SRC in capacitation-associated tyrosine phosphorylation of human spermatozoa Mol. Hum. Reprod., April 1, 2008; 14(4): 235 - 243. [Abstract] [Full Text] [PDF]
|
|