Transcriptomic changes induced by acute ozone in resistant and sensitive Medicago truncatulaaccessions

Abstract

Background: Tropospheric ozone, the most abundant air pollutant is detrimental to plant and animal health including humans. In sensitive plant species even a few hours of exposure to this potent oxidant (200-300 nL. L -1 ) leads to severe oxidative stress that manifests as visible cell death. In resistant plants usually no visible symptoms are observed on exposure to similar ozone concentrations. Naturally occurring variability to acute ozone in plants provides a valuable resource for examining molecular basis of the differences in responses to ozone. From our earlier study in Medicago truncatula, we have identified cultivar Jemalong is ozone sensitive and PI 464815 (JE154) is an ozone-resistant accession. Analyses of transcriptome changes in ozone-sensitive and resistant accession will provide important clues for understanding the molecular changes governing the plant responses to ozone.

The physiological, transcriptional and genetic responses of an ozone- sensitive and an ozone tolerant poplar and selected extremes of their F 2 progeny

“…Many of the differentially expressed genes identified here as being ozone-responsive, confirm previous studies on other species (Gupta et al, 2005;Li et al, 2006;Matsuyama et al, 2002;Puckette et al, 2008). Genes identified here are also more generally involved in abiotic stress responses.…”

“…This suggests that at the global scale, induced gene responses are conserved across species and that there appears to be a conserved general abiotic stress-induced remodelling of the transcriptome, in response to a variety of stresses. Genes encoding enzymes involved in the phenylpropanoid pathway were up-regulated as a result of ozone exposure, as was found in similar studies in a range of species (Koch et al, 2000;Ludwikow et al, 2004;Matsuyama et al, 2002;Puckette et al, 2008). Re-modelling of secondary metabolism is apparently an important and conserved mechanism of response to ozone exposure, and is a response that will divert energy from primary metabolism.…”

“…Concomitant with these symptoms is an up-regulation of defence and stress related genes and compounds (Conklin and Last, 1995;Lindroth, 2010;Ludwikow et al, 2004), and a down-regulation of photosynthetic components (Conklin and Last, 1995;Glick et al, 1995). Although transcriptional responses to ozone and underlying QTL have been studied in annual model and non-model species (Frei et al, 2008;Li et al, 2006;Overmyer et al, 2008;Puckette et al, 2008), there is currently limited knowledge in perennials, such as trees, which form the keystone species of many terrestrial ecosystems.…”

Proteomic and Transcriptomic Analysis of Aspergillus fumigatus on Exposure to Amphotericin B

“…Therefore, it was included as a control. The results obtained for the target genes were normalized using the threshold cycles (C T s) obtained for the GAPDH (control gene) cDNA amplifications run on the same plate by using the ⌬⌬C T method (39). The RT-PCR thermal cycling conditions consisted of an initial step at 50°C for 2 min, followed by 95°C for 10 min.…”

Effect of ozone and antioxidants on wheat and its pathogen — Bipolaris sorokininana

“…Adverse effects of O 3 on crops can be mitigated through application of O 3 protectants containing synthetic or natural antioxidants (Puckette et al 2008). Among antioxidants, natural antioxidants were preferred more than synthetic antioxidants for mitigating O 3 stress effect because of their environmental safety features.…”