Histochemical Analysis of Tissue-Specific α-Tubulin Acetylation as a Response to Autophagy Induction by Different Stress Factors in Arabidopsis thaliana

In order to study the role of posttranslational α-tubulin acetylation in the realization of stressinduced autophagy, levels of α-tubulin acetylation in Arabidopsis thaliana plants subjected to abiotic stress, such as salt and osmotic stresses, starvation, or ultraviolet B irradiation, were determined by Western blot analysis. It was shown a significant increase in the levels of acetylated α-tubulin under autophagy development, moreover, a synergistic action of stressful factors and E-64, an autophagy inhibitor, attenuated this increase. In order to study tissue-specific character of this modification, an immunohistochemical analysis of α-tubulin acetylation in A. thaliana seedlings was conducted. These experiments demonstrated the tissuespecific character of α-tubulin acetylation induced by stress, particularly, it is most markedly manifested in young and meristematic tissues, as well as in root tissues (root cap, epidermis and pericycle cells). Obtained results can serve as a proof of the regulatory role of α-tubulin acetylation in the realization of autophagy as an adaptive response to the influence of stressful stimuli.