Positional relationship between the gamete fusion site and the first division plane in the rice zygote.
In angiosperms, a zygote generally divides into a two-celled proembryo consisting of an apical and a basal cell that possess different cell fates. This first division of the zygote is a putative step in the formation of the apical-basal axis of the proembryo. The gamete fusion activates the egg, and the gamete fusion site on the zygote has been reported to provide a possible cue for subsequent zygotic development and/or embryonic patterning in animals and plants. In this study, the gamete fusion site on the rice zygote was labelled by in vitro fertilization of a rice egg cell with a fluorescence-stained sperm cell. The positional relationship between the gamete fusion site and the division plane formed by zygotic cleavage was monitored using a fixed culture of the fusion site-labelled zygote until the two-celled proembryo stage. The results indicate that gamete fusion sites exist on two-celled proembryos with no relation to the position of the first division plane, and that the gamete fusion site on the rice zygote does not function as a determinant for positioning the zygote division plane.
Nakajima
Keisuke
K
Department of Biological Sciences, Tokyo Metropolitan University, Minami-osawa Hachioji, Tokyo 192-0397, Japan.
Uchiumi
Takao
T
Okamoto
Takashi
T
D002455:Cell Division; D002459:Cell Fusion; D055993:Germ Cells, Plant / Q000166:cytology*; D012275:Oryza / Q000166:cytology*; D015053:Zygote / Q000166:cytology*
Development. 1996 May;122(5):1467-74
8625834
Development. 1989;107 Suppl:37-51
2699856
Plant Cell. 1997 Jul;9(7):1011-1020
12237373
Development. 2000 Feb;127(3):493-501
10631170
Sex Plant Reprod. 2010 Sep;23(3):211-7
20054584
Plant Cell. 1993 Oct;5(10):1349-1359
12271034
Planta. 2007 Aug;226(3):581-9
17361458
Nature. 2001 Jan 25;409(6819):517-21
11206548
Science. 2009 Mar 13;323(5920):1485-8
19286558
Proc Natl Acad Sci U S A. 2000 Sep 12;97(19):10643-8
10973479
Am J Bot. 1965 Mar;52:238-56
14285139
Nat Cell Biol. 2006 Jan;8(1):64-71
16378100
Curr Opin Plant Biol. 2006 Feb;9(1):41-7
16324880
Development. 2004 Feb;131(3):657-68
14711878
Nature. 2003 Nov 13;426(6963):147-53
14614497
Cell. 2004 Jan 9;116(1):109-19
14718171