| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Regular Article |
a Department of Anatomy and Cellular Biology, Sackler School of Biomedical Sciences,
b and the Department of Obstetrics and Gynecology, Tufts University School of Medicine and New England Medical Center, Boston, Massachusetts 02111
c Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Massachusetts 01003
Preovulatory, germinal vesicle (GV)-stage mouse oocytes are unable to undergo normal cortical granule (CG) secretion. Full secretory competence is observed by metaphase II (MII) of meiosis and involves the development of calcium response mechanisms. To identify the deficient or inhibited step in CG secretion, preovulatory GV-stage oocytes were stimulated and tested for their ability to undergo translocation, docking, and/or fusion. The mean CG distance to the plasma membrane was not reduced in fertilized or sperm fraction-injected, GV-stage oocytes relative to that in control GV-stage oocytes. In addition, analysis of individual CG distances to the plasma membrane indicated no subpopulation of CGs competent to translocate. Further analysis demonstrated that secretory incompetence likely is not due to a lack of proximity of CGs to the egg's primary calcium store, the endoplasmic reticulum. Calcium/calmodulin-dependent protein kinase II (CaMKII), which is reportedly involved in secretory granule translocation and secretion in many cells, including eggs, was investigated. A 60-kDa CaMKII isoform detected by Western blot analysis increased 150% during oocyte maturation. The CaMKII activity assays indicated that MII-stage eggs correspondingly have 110% more maximal activity than GV-stage oocytes. These data demonstrate that the primary secretory deficiency is due to a failure of CG translocation, and that a maturation-associated increase in CaMKII correlates with the acquisition of secretory competence and the ability of the egg to undergo normal activation.
1 Supported by grants from the Lalor Foundation (to A.L.A.), NICHD (HD 24191 to T.D.), and the U.S. Department of Agriculture (99-2371 and 97-2919 to R.A.F.).
2 Correspondence and current address: Tom Ducibella, Dept. of Obstetrics and Gynecology, New England Medical Center, Box 36, Boston, MA 02111. tom.ducibella{at}tufts.edu
This article has been cited by other articles:
|
|
 |
|
  J. E. Swain and T. B. Pool ART failure: oocyte contributions to unsuccessful fertilization Hum. Reprod. Update, September 1, 2008; 14(5): 431 - 446. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Tsaadon, R. Kaplan-Kraicer, and R. Shalgi Myristoylated alanine-rich C kinase substrate, but not Ca2+/calmodulin-dependent protein kinase II, is the mediator in cortical granules exocytosis Reproduction, May 1, 2008; 135(5): 613 - 624. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Matson, S. Markoulaki, and T. Ducibella Antagonists of Myosin Light Chain Kinase and of Myosin II Inhibit Specific Events of Egg Activation in Fertilized Mouse Eggs Biol Reprod, January 1, 2006; 74(1): 169 - 176. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 X.-Y. Liu, S.-F. Mal, D.-Q. Miao, D.-J. Liu, S. Bao, and J.-H. Tan Cortical granules behave differently in mouse oocytes matured under different conditions Hum. Reprod., December 1, 2005; 20(12): 3402 - 3413. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. Miyara, F.-X. Aubriot, A. Glissant, C. Nathan, S. Douard, A. Stanovici, F. Herve, M. Dumont-Hassan, A. L. Meur, P. Cohen-Bacrie, et al. Multiparameter analysis of human oocytes at metaphase II stage after IVF failure in non-male infertility Hum. Reprod., July 1, 2003; 18(7): 1494 - 1503. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. M. Wessel, S. D. Conner, and L. Berg Cortical granule translocation is microfilament mediated and linked to meiotic maturation in the sea urchin oocyte Development, March 11, 2003; 129(18): 4315 - 4325. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Tatone, S. Delle Monache, R. Iorio, D. Caserta, M. Di Cola, and R. Colonna Possible role for Ca2+ calmodulin-dependent protein kinase II as an effector of the fertilization Ca2+ signal in mouse oocyte activation Mol. Hum. Reprod., August 1, 2002; 8(8): 750 - 757. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
