Abstract

The effect of polyethylene glycol (PEG) on the transcript level of 512 stress-related genes was analyzed by cDNA microarray. Major changes in gene expression between control and PEG-treated embryos were observed during the initial stages of development, upon transfer of the embryogenic tissue on maturation medium, and during the late phases of development, culminating with the generation of cotyledonary embryos. Only small changes in gene expression were observed during the intermediate phases of embryo development. The transcript levels of several genes involved in cell aging and detoxification mechanisms, including peroxidases and chitinases, were developmentally regulated during the embryogenic process. Major differences in the expression of these genes were observed between control and PEG-treated embryos. Based on their expression profiles, four different clusters of genes involved in stress response mechanisms were identified. The first group of genes, which included several heat shock proteins, was up-regulated in PEG-treated immature embryos. An opposite tendency was observed for a second cluster of genes, which included a glutathione-S-transferase, and a cysteine protease. The third class included genes repressed by PEG in fully developed embryos, whereas a fourth group of genes, which included several heat shock proteins and ubiquitin, was induced in PEG-treated embryos at the end of the culture period. Difference in transcript levels and profiles of several genes involved in cell wall and lignin biosynthesis were also observed between control and PEG-treated embryos. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

Keywords

microarray; polyethylene glycol; transcript levels; white spruce

Published in

Plant Science
2003, Volume: 165, number: 4, pages: 719-729

UKÄ Subject classification

Biochemistry and Molecular Biology


Publication identifier

DOI: https://doi.org/10.1016/S0168-9452(03)00228-0

Permanent link to this page (URI)

https://res.slu.se/id/publ/88500