Drought and low temperature are the two most significant causes of abiotic stress in agricultural crops and, therefore, they pose considerable challenges in plant science. Hence, it is crucial to study response mechanisms and to select genes for identification signaling pathways that lead from stimulus to response. The assessment of gene expression is often attempted using real-time RT-PCR (qRT-PCR), a technique which requires a careful choice of reference gene(s) for normalization purpose. Here, we report a comparison of 13 potential reference genes for studying gene expression in the leaf and crown of barley seedlings subjected to low temperature or drought stress. All three currently available software packages designed to identify reference genes from qRT-PCR data (GeNorm, NormFinder and BestKeeper) were used to identify informative sets of up to three reference genes. Interestingly, the data obtained from the separate treatment of leaf and crown have led to the recommendations that HSP70 and S-AMD (and possibly HSP90) to be used as the reference genes for low-temperature stressed leaves, HSP90 and EF1α for low-temperature stressed crowns, cyclophilin and ADP-RF (and possibly ACT) for drought-stressed leaves, and EF1α and S-AMD for drought-stressed crowns. Our results have demonstrated that the gene expression can be highly tissue- or organ-specific in barley and have confirmed that reference gene choice is essential in qRT-PCR. The findings can also serve as guidelines for the selection of reference genes under different stress conditions and lay foundation for more accurate and widespread use of qRT-PCR in barley gene analysis.

• MeSH
• exprese genu MeSH
• fyziologický stres * MeSH
• ječmen (rod) genetika   fyziologie   MeSH
• listy rostlin genetika   fyziologie   MeSH
• nízká teplota MeSH
• období sucha MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• referenční standardy MeSH
• regulace genové exprese u rostlin * MeSH
• RNA rostlin genetika   MeSH
• rostlinné proteiny genetika   MeSH
• semenáček genetika   fyziologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Hormonal changes accompanying the cold stress (4°C) response that are related to the level of frost tolerance (FT; measured as LT50) and the content of the most abundant dehydrin, WCS120, were compared in the leaves and crowns of the winter wheat (Triticum aestivum L.) cv. Samanta and the spring wheat cv. Sandra. The characteristic feature of the alarm phase (1 day) response was a rapid elevation of abscisic acid (ABA) and an increase of protective proteins (dehydrin WCS120). This response was faster and stronger in winter wheat, where it coincided with the downregulation of bioactive cytokinins and auxin as well as enhanced deactivation of gibberellins, indicating rapid suppression of growth. Next, the ethylene precursor aminocyclopropane carboxylic acid was quickly upregulated. After 3-7 days of cold exposure, plant adaptation to the low temperature was correlated with a decrease in ABA and elevation of growth-promoting hormones (cytokinins, auxin and gibberellins). The content of other stress hormones, i.e., salicylic acid and jasmonic acid, also began to increase. After prolonged cold exposure (21 days), a resistance phase occurred. The winter cultivar exhibited substantially enhanced FT, which was associated with a decline in bioactive cytokinins and auxin. The inability of the spring cultivar to further increase its FT was correlated with maintenance of a relatively higher cytokinin and auxin content, which was achieved during the acclimation period.

• MeSH
• aklimatizace MeSH
• analýza hlavních komponent MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• listy rostlin enzymologie   MeSH
• nízká teplota MeSH
• oxidoreduktasy metabolismus   MeSH
• pšenice fyziologie   MeSH
• regulátory růstu rostlin metabolismus   MeSH
• roční období MeSH
• rostlinné proteiny metabolismus   MeSH
• zmrazování MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH