First Cleavage of the Mouse Embryo Responds to Change in Egg Shape at Fertilization
Abstract
Although mouse development is regulative, the cleavage pattern of the embryo is not random 1, 2. The first cleavage tends to relate to the site of the previous meiosis 3, 4. Sperm entry might provide a second cue, but evidence for 5, 6 and against 7, 8 this is indirect and has been debated 9, 10. To resolve whether sperm entry position relates to the first cleavage, we have followed development from fertilization by time-lapse imaging. This directly showed cytokinesis passes close to the site of the previous meiosis and to both the sperm entry site and trajectory of the male pronucleus in a significant majority of eggs. We detected asymmetric distribution of Par6 protein in relation to the site of meiosis, but not sperm entry. Unexpectedly, we found the egg becomes flattened upon fertilization in an actin-mediated process. The sperm entry position tends to lie at one end of the short axis along which cleavage will pass. When we manipulated eggs to change their shape, this repositioned the cleavage plane such that eggs divided along their experimentally imposed short axis. Such manipulated eggs were able to develop to term, emphasizing the regulative nature of their development.
Additional Information
© 2004 Cell Press. Published by Elsevier Under an Elsevier user license. Received 7 October 2003, Revised 18 December 2003, Accepted 20 January 2004, Available online 29 March 2004. We would like to thank Welcome Trust and BBSRC for supporting this work. M.Z.-G. is a Wellcome Trust Senior Research Fellow, and K.P. holds a Marie Curie Fellowship. We thank a number of our colleagues and friends for their support during the course of this work.Attached Files
Supplemental Material - 1-s2.0-S0960982204001058-mmc1.pdf
Supplemental Material - 1-s2.0-S0960982204001058-mmc2.mov
Supplemental Material - 1-s2.0-S0960982204001058-mmc3.mov
Supplemental Material - 1-s2.0-S0960982204001058-mmc4.mov
Supplemental Material - 1-s2.0-S0960982204001058-mmc5.mov
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Additional details
- Eprint ID
- 94823
- DOI
- 10.1016/j.cub.2004.02.031
- Resolver ID
- CaltechAUTHORS:20190419-105738331
- Wellcome Trust
- Biotechnology and Biological Sciences Research Council (BBSRC)
- Marie Curie Fellowship
- Created
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2019-04-23Created from EPrint's datestamp field
- Updated
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2021-11-16Created from EPrint's last_modified field