ENDOCYTOSIS AND ITS INHIBITORS IN BASIDIOMYCETOUS FUNGUS RHIZOCTONIA SOLANI

Endocytosis is a complex process of absorption from the external environment and further distribution within the cell of soluble substances, macromolecules, microparticles, and etc. which occurs with the participation of vesicles formed by the cytoplasmic membrane. Endocytosis in the cells of animals and humans is actively and successfully explored. Thus, the classification of this process in animals, based only on the characteristics of the formation of primary vesicles, includes up to ten different ways of endocytosis. Modern knowledge of endocytosis in mycelial fungi is not so extensive, so its study in this group of organisms is an actual and promising direction in fundamental and applied mycology. In the present work, we investigated the effect of six different inhibitors, acting both on the assembly of actin/tubulin cytoskeletons and on the formation of different types of endocytosis, on the dynamics of endocytosis in the phytopathogenic heterobasidial fungus Rhizoctonia solani The effect of inhibitors was evaluated by microscopic analysis of the mycelial cell absorption of a fluorescent marker of endocytosis AM4-64. As a result of the study, four types of inhibitor effects on R. solani endocytosis were revealed: from complete absence of action to severe suppression of different stages of fungal endocytosis. Four of the six inhibitors, used to inhibit endocytosis in animals and humans, have a suppressing effect on the endocytosis of the heterobasidial fungus R. solani, which indicates the conservative nature of individual mechanisms of endocytosis in the examined fungus and, possibly, in mycelial fungi as a whole. Various hypotheses on the principles of the action of the studied inhibitors on the endocytosis activity of fungi are proposed.

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