spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow References
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Mohri, T.
Right arrow Articles by Ikegami, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Mohri, T.
Right arrow Articles by Ikegami, S.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

Development, Vol 125, Issue 2 293-300, Copyright © 1998 by Company of Biologists

JOURNAL ARTICLES

Sperm-induced local [Ca2+]i rise separated from the Ca2+ wave in sea urchin eggs in the presence of a gamete fusion inhibitor, jaspisin

T Mohri, S Miyazaki, H Shirakawa and S Ikegami
Department of Molecular Physiology, National Institute for Physiological Sciences, Okazaki, Japan. tsmohri@nips.ac.jp

An increase in intracellular Ca2+ concentration ([Ca2+]i) at a focal plane was recorded simultaneously with sperm-egg binding and membrane current upon insemination of sea urchin Hemicentrotus pulcherrimus eggs. No change in current and [Ca2+]i occurred in the presence of jaspisin, a novel substance that inhibits metallo-endoproteinase and sperm-egg membrane fusion (S. Ikegami, H. Kobayashi, Y. Myotoishi, S. Ohta and K. H. Kato (1994) J. Biol. Chem. 269, 23262-23267). With low doses of jaspisin, a spermatozoon first produced a step inward current (I(on)) as an indication of gamete membrane fusion and then induced a local [Ca2+]i rise at the site of sperm attachment 6-10 seconds after I(on). The sperm, however, soon detached from the egg. Increasing inward current was abruptly cut off (I(off)) within 9-15 seconds and the local [Ca2+]i rise began to decline 1-3 seconds after I(off). In most cases, no further responses or an elevation of fertilization envelope (FE) occurred. In some cases, [Ca2+]i at the sperm attachment site increased again even after the sperm detached and triggered a Ca2+ wave which caused an activation current and FE formation. This recording of a gamete membrane-fusion-induced local [Ca2+]i rise, separated from the Ca2+ wave, is a key phenomenon for elucidating the initial sperm stimulation of the egg at fertilization.
Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?


This article has been cited by other articles:


Home page
 Physiol. Rev.Home page
M. Whitaker
Calcium at Fertilization and in Early Development
Physiol Rev, January 1, 2006; 86(1): 25 - 88.
[Abstract] [Full Text] [PDF]

Home page
 DevelopmentHome page
K Kyozuka, R Deguchi, T Mohri, and S Miyazaki
Injection of sperm extract mimics spatiotemporal dynamics of Ca2+ responses and progression of meiosis at fertilization of ascidian oocytes
Development, January 10, 1998; 125(20): 4099 - 4105.
[Abstract] [PDF]


© The Company of Biologists Ltd 1998