Cold-modulated leaf compounds in winter triticale DH lines tolerant to freezing and

Abstract

Tolerance to freezing and seedling diseases caused by Microdochium spp. is an essential trait for the wintering of triticale (×Triticosecale Wittmack) and other cereals. Preceding multi-year studies indicate that after long-term exposure to the low temperature, cereal seedlings acquire a genotype-dependent cross-tolerance to other subsequent stresses. This paper presents the first non-gel protein profiling performed via high performance liquid chromatography coupled with Mass Spectrometry as well as Fourier Transform-Raman spectroscopy measurements performed directly on leaves of triticale seedlings growing under different conditions. The research used doubled haploid lines selected from the mapping population, with extreme tolerance/susceptibility to freezing and M. nivale infection. These non-targeted methods led to the detection of twenty two proteins cold-accumulated in the most tolerant seedlings in relation to susceptible ones, classified as involved in protein biosynthesis, response to different stimuli, energy balancing, oxidative stress response, protein modification, membrane structure and anthocyanin synthesis. Additionally, in seedlings of the most freezing- and M. nivale-tolerant line, cold-hardening caused decrease of the carotenoid and chlorophyll content. Moreover, a decrease in the band intensity typical for carbohydrates as well as an increase in the band intensity characteristic for protein compounds were detected. Both studied lines revealed a different answer to stress in the characteristics of phenolic components.

Temperature-Caused Changes in Raman Pattern and Protein Profiles of Winter Triticale (x Triticosecale, Wittm.) Field-Grown Seedlings

“…Hewo seedlings analyzed using 2D SDS PAGE protein profiling, a cold-mediated accumulation of peroxiredoxin content was observed [12]. Similarly, in studies conducted on the influence of temperature on seedlings of the DH1 line in controlled conditions, increases in the relative expression of the gene encoding peroxiredoxin and the relative content of this protein were observed, estimated by the qRT-PCR and LC-MS techniques, respectively [10,14]. In pre-hardened seedlings, the mean relative abundance of the PsbB protein was higher in the DH3 and cv.…”

“…Based on the amino acid sequences identified in our previous studies [14], the location of the coding genes for the specific proteins described in this work was in silico located, both in the wheat (chr1D, chr2A-D, chr3A-D, chr4A-B, chr5D, chr6A, and D, as well as chr7A and D) and rye genomes (chr2R-7R). The highest number of candidate genes was found on chromosomes 2A-D and 2R (Table S5).…”

“…is a synthetic hybrid derived by crossing between wheat (Triticum aestivum L., AABBDD) and rye (Secale cereale L., RR); consequently, it contains both wheat (AABB or AABBDD) and rye (RR) genomes, whereas the D genome is fully eliminated during the breeding process [8]. Currently cultivated, hexaploid triticale (AABBRR) is well-adapted to adverse environmental conditions: low temperatures [2,[9][10][11][12][13][14][15], aluminum toxicity [16], drought [1], salinity [17], and waterlogged soils [18]. All of these qualities make triticale a very promising cereal and a valuable genetic source for transferring desirable genes, in particular stress-tolerance genes from rye to wheat [8].…”

“…The Raman profiles of winter triticale cold-chamber-tested seedlings were also differentiated under the influence of temperature changes [14]. Raman spectroscopy was established as an alternative to other expensive and time-consuming techniques (e.g., chromatography).…”

“…In turn, the technique of gel electrophoresis combined with electrotransfer and immunostaining allows for the quantitative and qualitative analysis of the individual protein abundance in the tested samples, and then a comparison of the protein profiles between the objects. In previous studies, antioxidant enzymes, in particular peroxidases, Glutathione-S-Transferases, and thioperoxiredoxins, were identified by a proteomic approach as being involved in maintaining the balance of oxido-reduction processes during winter triticale, barley cold acclimation, and tolerance to the following stresses [11,12,14,32,33]. In winter barley seedlings, highly differentiated in terms of freezing tolerance, changes in protein abundance related to photosynthesis, carbohydrate metabolism, oxidation-reduction reactions, and stress response were observed under the influence of cold hardening.…”