The article raises the problems of intracellular spatial and temporal organization of metabolism, signaling, and energy supply of these processes. To provide cell functions, the enzymes of metabolic chains, molecules of signaling pathways, and macroergs (as units of molecular interactions, accompanied by energy consumption) should find their partners and get their precise spatial relationship. The current views are based on ideas of compartmentalization of all processes as local sites of cellular matrix membrane, where specific stages of different metabolic cycles take place. The assembly of complexes of macromolecules in the number and combinations, required for their adequate functioning in the space of a cell, is generally described as intracellular transport of vesicles, implemented by mobile elements of cytoske-leton. Inside the vesicle there is «effective load»-macromolecules. The membranes of these vesicles fuse with specific sites of the matrix membranes and therefore relocate macromolecules. Neither calculations nor assumptions allow explaining precise formation of enzymatic chains, their interaction, signaling, etc. on this basis. Such transport of macromolecules (inside vesicles) enables solving other tasks. The concept of search-and-address systems in the form of space-scanning micro vesicles is proposed and well-grounded for purposes of searching for partners, forming chains and complexes, and building compartments. The micro vesicles collect corresponding chains of enzymes, signaling, and ensure the interactions on their surface. These micro vesicles are exactly those compartments, which provide for both precision of processes and their relationship.

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The idea about intracellular transport of metabolic products is presented considering two constituents. The first was described in general in the previous publication. It justified the thesis that cell metabolism is localized and realized not on the fixed structures but on the vigorously and steadily moving («prowling») microvesicles. In the current paper we have shown that an addition of tetrazolium (MTT) to mesenchymal stem cells (MSC) leads to the cumulation of formazan on the surface of actively moving vesicles. This process was time-tracked and shown in dynamics. As formazan is a metabolite product, its formation on the vesicles is an experimental confirmation of the metabolic processes on these moving structures. The second constituent is presented as a hypothesis that is based on the literature data on the intracellular electrical potentials and the calculations of their possible involvement in precision transport of metabolic products

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