Aluminium‐responsive genes in sugarcane: identification and analysis of expression under oxidative stress

• Published in: Journal of experimental botany 2003-04, Vol.54 (385), p.1163-1174
• Main Author: Watt, Derek A.
• Format: Article
• Language: English
• Subjects: Adaptation, Physiological - drug effects; Adaptation, Physiological - genetics; Aluminum; Aluminum - pharmacology; Biological and medical sciences; Complementary DNA; Diamide - pharmacology; DNA, Complementary - genetics; Expressed Sequence Tags; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant - drug effects; Genes; Genetic hybridization; Hybridization, Genetic; Key words: Aluminium; Metabolism; Metabolism. Physicochemical requirements; Oxidative Stress; Plant physiology and development; Plant roots; Plant Roots - drug effects; Plant Roots - genetics; Plant Roots - metabolism; Plants; Poaceae - genetics; Research Papers: Cell and Molecular Biology, Biochemistry and Molecular Physiology; Root growth; Root tips; Saccharum - drug effects; Saccharum - genetics; Saccharum - metabolism; Signal Transduction - drug effects; Sugar cane; sugarcane; suppression subtractive hybridization
• ISSN: 0022-0957; 1460-2431
• DOI: 10.1093/jxb/erg128

Suppression subtractive hybridization (SSH) technology was used to gain preliminary insights into gene expression induced by the phytotoxic aluminium species, Al3+, in sugarcane roots. Roots of hydroponically‐grown Saccharum spp. hybrid cv. N19 were exposed to 221 µM Al3+ at pH 4.1 for 24 h, a regime shown to inhibit root elongation by 43%, relative to unchallenged roots. Database comparisons revealed that, of a subset of 50 cDNAs ostensibly up‐regulated by the metal in the root tips, 14 possessed putative identities indicative of involvement in signalling events and the regulation of gene expression, while the majority (28) were of unknown function. All of the 50 cDNAs sequenced displayed significant similarity to uncharacterized plant expressed sequence tags (ESTs), approximately half (23) of which had been derived from other graminaceous crop species that had been subject to a variety of stresses. Analysis of the expression of 288 putative Al3+‐inducible genic fragments indicated higher levels of expression under oxidative (1 mM diamide for 4 h) rather than Al3+ stress. By deploying SSH, this study has provided an indication of the nature of genes expressed in sugarcane roots under Al3+ stress. It is anticipated that the information obtained will guide further exploration of the potential for manipulation of the Al tolerance characteristics of the crop.