JXB Advance Access originally published online on December 6, 2004
Journal of Experimental Botany 2005 56(412):633-644; doi:10.1093/jxb/eri035
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
Tight regulation of expression of two Arabidopsis cytosolic Hsp90 genes during embryo development


Laboratory of Molecular Biology, Department of Agricultural Biotechnology, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece
To whom correspondence should be addressed. Fax: +30 210 529 4321. E-mail: phat{at}aua.gr
The spatial and temporal distribution of expression of two cytosolic members of the AtHsp90 gene family was assessed during early development. In stressed transgenic plants bearing the AtHsp90-3 promoter, ß-glucuronidase (GUS) activity was strong in meristematic tissues. Expression was also detected in vascular tissues, leaf veins, siliques, and in pollen sacs. The promoter induced gene expression after heat shock in a time-course dependent manner. AtHsp90-1 promoter activity was low throughout the early stages of embryo development but high just before embryo maturation, with expression most prominent in cotyledons. AtHsp90-3 promoter activity was almost constant and restricted to the root and the cotyledon tips of the embryo. This highly specific spatial distribution of GUS activity changed when the tissues were heat-stressed. Both promoters were also active in unstressed mature pollen grains and during pollen germination. The results shown here indicate that different regulatory and developmental mechanisms control and differentiate the expression of the two cytosolic members of the Arabidopsis AtHsp90 gene family under normal conditions. The developmental and restricted pattern of expression of the AtHsp90-1 and 3 gene promoters in unstressed transgenic plants suggest prominent and distinctive roles of these two genes during different developmental processes.
Key words: Arabidopsis, Hsp90 genes, pollen and embryo expression, promoter analysis
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
D. Samakovli, A. Thanou, C. Valmas, and P. Hatzopoulos Hsp90 canalizes developmental perturbation J. Exp. Bot., October 1, 2007; 58(13): 3513 - 3524. [Abstract] [Full Text] [PDF] |
||||
