Human Reproduction, Vol. 17, No. 7, 1839-1845,
July 2002
© 2002 European Society of Human Reproduction and Embryology
Trophectoderm growth and bilateral symmetry of the blastocyst in the mouse
Mammalian Development Laboratory, University of Oxford, Department of Zoology, South Parks Road, Oxford OX1 3PS, UK
BACKGROUND: The present study was undertaken to ascertain whether the polarized flow of cells from polar to mural trophectoderm is related to the axis of bilateral symmetry of the blastocyst in the mouse, and whether trophectoderm cells can initiate new cycles once they have left the polar region. METHODS AND RESULTS: Two different approaches were used to investigate the relationship of polar to mural flow of trophectoderm cells to the bilateral axis. One was to mark peripheral polar trophectoderm cells at one or both ends of the bilateral axis in early blastocysts and examine the distribution of their clonal descendants after further growth in culture. The other was to mark the two ends of the bilateral axis with small oil drops in the zona pellucida in blastocysts whose polar trophectoderm was then labelled globally with fluorescent latex microspheres before culture. In both cases, marking of additional blastocysts orthogonal to the bilateral axis was also done. The results show that the direction of polar to mural flow of cells is not random, and that the most distal mural trophectoderm cell could yield up to eight descendants during 45 h of culture. CONCLUSION: The findings are consistent with the polar to mural flow of trophectoderm cells being aligned with the bilateral axis. Moreover, trophectoderm cells can embark on new cycles even when remote from the inner cell mass.
Key words: bilateral symmetry/mouse blastocyst/mural trophectoderm/polarized growth/polar trophectoderm
1 To whom correspondence should be addressed. E-mail: richard.gardner{at}zoology.ox.ac.uk
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
T. Fujimori, Y. Kurotaki, K. Komatsu, and Y.-i. Nabeshima Morphological Organization of the Mouse Preimplantation Embryo Reproductive Sciences, February 1, 2009; 16(2): 171 - 177. [Abstract] [PDF] |
||||
![]() |
M. Bischoff, D.-E. Parfitt, and M. Zernicka-Goetz Formation of the embryonic-abembryonic axis of the mouse blastocyst: relationships between orientation of early cleavage divisions and pattern of symmetric/asymmetric divisions Development, March 1, 2008; 135(5): 953 - 962. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Kurotaki, K. Hatta, K. Nakao, Y.-i. Nabeshima, and T. Fujimori Blastocyst Axis Is Specified Independently of Early Cell Lineage But Aligns with the ZP Shape Science, May 4, 2007; 316(5825): 719 - 723. [Abstract] [Full Text] [PDF] |
||||
![]() |
R.L. Gardner The axis of polarity of the mouse blastocyst is specified before blastulation and independently of the zona pellucida Hum. Reprod., March 1, 2007; 22(3): 798 - 806. [Abstract] [Full Text] [PDF] |
||||
![]() |
R.L. Gardner Experimental analysis of second cleavage in the mouse Hum. Reprod., December 1, 2002; 17(12): 3178 - 3189. [Abstract] [Full Text] [PDF] |
||||



