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Leszczuk, A.

Publications and source records attributed to Leszczuk, A..

3 recordsLinked to original sources

Immunovisualization of spatial changes in leaves and root tissue associated with drought stress in wheat (Triticum aestivum L.)

Background and AimsPlants have evolved complex cell-type-specific processes to adapt to a dynamic environment, exhibiting distinct signals in response to emerging drought stress. We propose an advanced qualitative and quantitative analysis approach, demonstrating tissue specificity in drought adaptation, which in turn may provide novel biological insights. MethodsWe performed immunofluorescence labeling of specific cellular components in situ, and the acquired data were analyzed in terms of changes in quantitative and spatial fluorescence intensity. ResultsThe qualitative analysis revealed differences in terms of individual components and individual days of the experiment. The quantitative analysis of leaf anatomy showed that the most pronounced changes were observed in the level of proteoglycans (JIM13, JIM15) and polysaccharides (LM5, LM16, LM20). The leaves of plants growing in drought were characterized by destroyed fragments, in which increased secretion of extensins, AGPs, galactans, hemicelluloses, and RG-I was noted. In turn, the qualitative analyses of the microscopy images of roots, along with fluorescence intensity analyses, revealed a significantly higher content of AGP and arabinoxylan in the exodermis in plants grown under drought stress. ConclusionOur research has revealed that the changes at the tissue level are targeted and highly specific. The obtained results also emphasize the importance of in planta analyses, which indicate that findings from only single ex planta studies may distort the entire image of changes occurring in the plant as a result of stress. HIGHLIGHT STATEMENTOne of the strategies employed by plants to mitigate the effects of water loss is the mechanical protection of organs through targeted and highly specific modifications in their cellular architecture.

plant biology↗

Dynamic structural changes in wheat vegetative development as an adaptive response to drought stress

Background and AimsThe objective of our research was to define the precise structural response in wheat seedlings correlated with the duration of drought stress. For this purpose, we selected structural components of the cell recognised by specific molecular probes, which are molecules involved in rapid spatial cellular rearrangements: hydroxyproline-rich glycoproteins, xylan, and pectic compounds. MethodsUsing basic molecular techniques, we identified the transformations occurring within the cell and elucidated the mechanism triggered by growth in the absence of water. ResultsOur general observations are as follows: 1) remodelling of the cell wall after just 5 days of drought conditions; 2) organ-specific responses for drought resistance; 3) drought triggers the aggregation or cross-linking of molecules in the cell wall (appearance of larger molecular mass fractions) and causes degradation or breakdown of cell wall components (appearance of low molecular masses); 4) changes in the elemental economy due to modifications in cellular assembly. ConclusionOur finding of the deposition of un- and esterified homogalacturonans (HGs) and AGPs indicates reconstruction of cell wall as a means of prevention of drought effects. A stress-induced higher level of unesterified HGs permits calcium cross-linking, which enhances cell wall rigidity and helps in intracellular water preservation. Highlight statementDynamic changes in wheat as a response to drought include remodelling of the cell wall after 5 days of drought,modification in the elemental composition, deposition of HGs, xylan, and AGP.

plant biology↗

The modified activity of prolyl 4 hydroxylases (P4Hs) reveals the effect of arabinogalactan proteins (AGPs) on changes in the cell wall during the tomato ripening process

Arabinogalactan proteins (AGPs) are proteoglycans with an unusual molecular structure characterised by the presence of a protein part and carbohydrate chains. Their specific properties at different stages of the fruit ripening programme make AGPs unique markers of this process. An important function of AGPs is to co-form an amorphous extracellular matrix in the cell wall-plasma membrane continuum; thus, changes in the structure of these molecules can determine the presence and distribution of other components. The aim of the current work was to characterise the molecular structure and localisation of AGPs during the fruit ripening process in transgenic lines with silencing and overexpression of SlP4H3 genes. The objective was accomplished through comprehensive and comparative in situ and ex situ analyses of AGPs from the fruit of transgenic lines and wild-type plants at specific stages of ripening. The experiment showed that changes in P4H3 activity affected the content of AGPs and the progress in their modifications in the ongoing ripening process. The analysis of the transgenic lines confirmed the presence of AGPs with high molecular weights (120-60 kDa) at all the examined stages, but a changed pattern of the molecular features of AGPs was found in the last ripening stages, compared to WT. In addition to the AGP molecular changes, morphological modifications of fruit tissue and alterations in the spatio-temporal pattern of AGP distribution at the subcellular level were detected in the transgenic lines with the progression of the ripening process. The work highlights the irreversible impact of AGPs and their alterations on the fruit cell wall assembly and changes in AGPs associated with the progression of the ripening process. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=96 SRC="FIGDIR/small/576594v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@4291e4org.highwire.dtl.DTLVardef@780fdeorg.highwire.dtl.DTLVardef@59c14borg.highwire.dtl.DTLVardef@a12735_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗