Gel‐based proteomics reveals potential novel protein markers of ozone stress in leaves of cultivated bean and maize species of Panama

Abstract

We examined responses of cultivated bean (Phaseolus vulgaris L. cv. IDIAP R-3) and maize (Zea mays L. cv. Guarare 8128) plants exposed to ozone (O(3)) using a leaf injury assessment and proteomics approach. Plants grown for 16 days in greenhouse were transferred to an O(3) chamber and exposed continuously to 0.2 ppm O(3) or filtered pollutant-free air for up to 72 h. CBB-stained gels revealed changes in ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) protein. By Western analysis changes in marker proteins for O(3) damage in leaves by 1-DE were checked. In bean leaves, two superoxide dismutase (SOD) protein (19 and 20 kDa) were dramatically decreased, while ascorbate peroxidase (APX, 25 kDa), small heat shock protein (HSP, 33 kDa), and a naringenin-7-O-methyltransferase (NOMT, 42 kDa) were increased by O(3). In maize leaves, expression levels of catalase (increased), SOD (decreased), and APX (increased) were drastically changed by O(3) depending on the leaf stage, whereas crossreacting HSPs (24 and 30 kDa) and NOMT (41 kDa) proteins were strongly increased in O(3)-stressed younger leaves. These results indicated a clear modulation of oxidative stress-, heat shock-, and secondary metabolism-related proteins by O(3). Finally, 2-DE at 72 h after O(3) exposure revealed changes (induction/suppression) in expression levels of 25 and 12 protein spots in bean and maize leaves, respectively. Out of these, ten and nine nonredundant proteins in bean and maize, respectively, were identified by MS. A novel pathogenesis-related protein 2 may serve as a potential marker for O(3) stress in bean.

Analysis of environmental stress response on the proteome level

“…They rely on MS measurements with relatively low mass accuracy (MALDI-TOF and ion traps) for protein identification (Zubarev and Mann, 2007). For example, one can often see database searches conducted with a 1-1.5 Da window for the precursor mass and 0.5-1 Da tolerance for the fragment ions (Bhushan et al, 2007;Lantz et al, 2007;Torres et al, 2007). It is obvious that database searching of experimental data using wider mass windows inevitably leads to increased numbers of identifications, which are not necessarily correct.…”

“…Only recently false positive identification has become an issue in environmental proteomics (Lacerda, Choe, & Reardon, 2007;Nesatyy et al, 2007) and the publication of lists of identified proteins without additional validation is still widespread (Bhushan et al, 2007;Santos et al, 2007;Torres et al, 2007;Wang et al, 2008). It also appears that most scientists in the field did not make use of integrated pipelines, such as CPAS and TPP, for the analysis of proteomics data, preferring to use the stand-alone commercial packages SEQUEST and MASCOT.…”

Impacts of Ozone (O3) and Carbon Dioxide (CO2) Environmental Pollutants on Crops: A Transcriptomics Update

“…Being a C 4 crop, its response to climate change has been always been a bit different from the other plants/crops. Torres et al (2007) have performed a detailed investigation of O 3 response in maize (cv. Guarare 8128) plants through gel-based proteomics approach.…”

Comparative analysis of seed transcriptomes of ambient ozone-fumigated 2 different rice cultivars

“…3,[9][10][11][12][13] The adverse effect of O 3 on yield of the crops thus becomes a serious problem under a ground-level O 3 "predicted to increase" in the future. Thus, to gain an insight into the adverse effects and a clue for early diagnosis and prevention of O 3 symptoms, many research groups have been identifying O 3 -responsive genes, proteins, or metabolites in aspen, 14,15 birch, 16,17 pepper, 18 Arabidopsis, 19,20 bean, 21 maize, 21 and rice. [22][23][24][25][26] These experiments utilize the power of "OMICS" providing clues to establish cellular response networks to O 3 stress.…”