Synthesis of plasma membrane proteins in cells of the regenerating liver

Protein synthesis was studied by determining incorporation of [³H]glycine in cells of the regenerating rat liver. The rate of incorporation of [³H]glycine into total liver proteins, proteins of the microsomal fraction and of the hyaloplasm, and proteins of the plasma membranes, soluble and insoluble in 0.05 M K₂CO₃ was determined. The rate of incorporation of [³H]glycine into soluble proteins of the plasma membranes reached a maximum 1 h after partial hepatectomy. The maximal rate of synthesis of proteins of the other fractions occurred at the end of the g₁ period. The sharp increase in the rate of synthesis of plasma membrane proteins soluble in 0.05 M K₂CO₃ is evidently one of the earliest biochemical events in cells of the regenerating liver preparing to divide.Laboratory of Chemical Factors of Regulation of Growth and Cell Division, Institute of Biological and Medical Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Orekhovich.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 589–591, May, 1978.