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Updated: Jul 30, 2026

Studying Protein Import into Chloroplasts Using Protoplasts
Published on: December 10, 2018
Protoreaction of protoplasm
1Laboratory of Cell Physiology, Institute of Cytology, Russian Academy of Sciences, Tikhoretsky Ave 4, St. Petersburg 194064, Russia. vladimir.matveev@gmail.com
Abstract:
My goal is to describe briefly the universal cellular reaction (UCR) to external actions and agents. This general reaction was the main subject of investigation by the scientific school of the outstanding Russian cytologist, Dmitrii Nasonov (1895-1957). The UCR consists of two phases of complex changes in cellular viscosity and turbidity, in the cell's ability to bind vital dyes, in the resting membrane potential, and in cellular resistance to harmful actions. Works from the Nasonov School have shown that these changes are based on structural-functional transformations of many cell proteins that react uniformly to actions of different physical and chemical nature. In general, these complex changes do not depend on cell type, indicating the universal and ancient nature of the UCR as well as its general biological significance. A new interpretation of the mechanism of the universal reaction is proposed in this paper, and a possible role for contractile proteins in the mechanism of the UCR of muscle cells is presented. In addition, the concept of cell hydrophobicity is introduced. Nasonov's School proposed a concept of physiological standardization that allows comparison of data obtained by different investigators and that will also be described here.
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