Interaction of actin with the enzymes of carbohydrate metabolism.

As was shown earlier, actin is present not only in muscles, but in other animal tissues as well. Now it is firmly established that actin is built into cytoskeleton structures and is a necessary component of all kinds of eukaryotic cells. As is known, the main functions of the cytoskeleton are maintenance of the cell form and participation in the motile processes. At the same time a lot of information is available which indicates the regulatory role of actin in carbohydrate metabolism. The interaction of F-actin with most of the muscle glycolytic enzymes which are located in the region of actin filaments was shown in vitro. In particular, it was established that F-actin forms a complex with glyceraldehyde phosphate dehydrogenase and increases its activity. F-actin interacts with lactate dehydrogenase, forming a complex in which one molecule of the enzyme binds four actin monomers. The formation of the complex results in inhibition of lactate dehydrogenase activity. And, finally, F-actin has a strong activating effect on cellulase which belongs to the other enzyme system. Now the information is available on the induction of cellulase gene expression accompanied by an increase in actin synthesis. These results prove the opinion that actin is a coordinator of carbohydrate metabolism in the cell.