Monitoring the Expression of Maize Genes in Developing Kernels under Drought Stress using Oligo‐microarray

Abstract

Preharvest aflatoxin contamination of grain grown on the US southeastern Coast Plain is provoked and aggravated by abiotic stress. The primary abiotic stress is drought along with high temperatures. The objectives of the present study were to monitor gene expression in developing kernels in response to drought stress and to identify drought-responsive genes for possible use in germplasm assessment. The maize breeding line Tex6 was used, and gene expression profiles were analyzed in developing kernels under drought stress verses well-watered conditions at the stages of 25, 30, 35, 40, 45 d after pollination (DAP) using the 70 mer maize oligo-arrays. A total of 9 573 positive array spots were detected with unique gene IDs, and 7 988 were common in both stressed and well-watered samples. Expression patterns of some genes in several stress response-associated pathways, including abscisic acid, jasmonic acid and phenylalanine ammonia-lyase, were examined, and these specific genes were responsive to drought stress positively. Real-time quantitative polymerase chain reaction validated microarray expression data. The comparison between Tex6 and B73 revealed that there were significant differences in specific gene expression, patterns and levels. Several defense-related genes had been downregulated, even though some defense-related or drought responsive genes were upregulated at the later stages.Luo M, Liu J, Lee RD, Scully BT, Guo BZ (2010) Monitoring the expression of maize genes in developing kernels under drought stress using oligo-microarray.

Tackling Drought Stress: RECEPTOR-LIKE KINASES Present New Approaches

“…The plant's transcriptional changes during drought stress have been extensively studied in a wide range of species, including Arabidopsis (Seki et al, , 2002Kilian et al, 2007;Huang et al, 2008;Matsui et al, 2008), oilseed rape (Brassica napus) , rice (Oryza sativa) (Lenka et al, 2011;, maize (Luo et al, 2010;Chen et al, 2011), loblolly pine (Pinus taeda) (Lorenz et al, 2011), and banana (Musa spp) (Davey et al, 2009). Analyses of gene expression, transcriptional regulation, and signal transduction in plants subjected to drought treatments have revealed pathways involved in plant response to water stress Abe et al, 2003;Tran et al, 2004).…”

“…Large numbers of signaling genes are regulated by drought stress in, for example, maize (Luo et al, 2010;Chen et al, 2011), but approaches to modify their activities in maize and other crops remain scarce. Furthermore, most of the genetically modified lines that have been developed to better withstand drought and other stress conditions have yet to be tested in the field (Tognetti et al, 2006;Nelson et al, 2007;Vanderauwera et al, 2007;Castiglioni et al, 2008).…”

Development of Maize Host Resistance to Aflatoxigenic Fungi

“…Similar work had previously been performed using Tex6 as the resistant line and B73 as the susceptible [74], however, in the study using closely-related lines, imbibed mature kernels were used (for the first time) and proved to be a quicker and easier approach than traditional approaches. The involvement of certain stress-related and antifungal genes previously shown to be associated with constitutive resistance was demonstrated here; a kinase-binding protein, Xa21 was highly up-regulated in the resistant line compared to the susceptible, both constitutively and in the inducible state.…”

Genetic improvement of rice for biotic and abiotic stress tolerance

“…Several proteins, antioxidants, and compatible solutes are produced in response to stress conditions. Many crop plants have been developed by overexpression of genes responsible for these compounds and evaluated for various abiotic stresses under laboratory and field conditions (Luo et al, 2010).…”