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

Background and Aims Plants 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. Methods We 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. Results The 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. Conclusion Our 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.