EFFECT OF HEAT-SHOCK ON CYTOPLASMIC PROTEIN-SYNTHESIS IN PEA (PISUM-SATIVUM L) LEAVES

The effect of heat shock on cytoplasmic protein synthesis was studied in pea leaves. Heat shock treatment decreased the polysomic fraction a nd increased the monosomic fraction of the total ribosomal pool in pea seedlings. This is characteristic of leaves of various physiological states including growing, non-growing, and aging. However, the heat sh ock response of young leaves was more pronounced. The spectrum of poly somal proteins was analyzed by electrophoresis. In preparations isolat ed from plants subjected to heat shock, a 70 kD protein was not detect ed. The possible nature and function of this protein are discussed.