title: Changes in gene expression in maize kernel in response to water and salt stress.
abstract: Increasing pressure on limited water resources for agriculture, together with the global temperature increase, highlight the importance of breeding for drought-tolerant cultivars. A better understanding of the molecular nature of drought stress can be expected through the use of genomics approaches. Here, a macroarray of approximately 2500 maize cDNAs was used for determining transcript changes during water- and salt-stress treatments of developing kernels at 15 days after pollination. Normalization of relative transcript abundances was carried out using a human nebulin control sequence. The proportions of transcripts that changed significantly in abundance upon treatment (>2-fold compared to the control) were determined; 1.5% of the sequences examined were up-regulated by high salinity and 1% by water stress. Both stresses induced 0.8% of the sequences. These include genes involved in various stress responses: abiotic, wounding and pathogen attack (abscisic acid response binding factor, glycine and proline-rich proteins, pathogenesis-related proteins, etc.). The proportion of down-regulated genes was higher than that for up-regulated genes for water stress (3.2%) and lower for salt stress (0.7%), although only eight genes, predominantly involved in energy generation, were down-regulated in both stress conditions. Co-expression of genes of unknown function under defined conditions may help in elucidating their roles in coordinating stress responses.
authors.affiliation: Max Planck Institute for Plant Breeding Research, Carl von Linne Weg 10, 50829 Cologne, Germany. avioleta@mrizp.co.yu
authors.forename: Violeta
authors.initials: V
authors.lastname: Andjelkovic
authors.forename: Richard
authors.initials: R
authors.lastname: Thompson
mesh_terms: D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012492:Salts / Q000494:pharmacology*; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D014867:Water / Q000494:pharmacology*; D003313:Zea mays / Q000033:anatomy & histology / Q000187:drug effects* / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D012492:Salts; D014867:Water