Ribonuclease activities in developing experimental granulation tissue with reference to polysomes

Abstract

The Mg2+-precipitable polysomes in experimental granulation tissue increase up to three weeks and decrease slowly thereafter. Polysomes from young granulation tissue are, on a weight basis, more active in cell-free protein synthesis than polysomes from old granulation tissue. RNase activity is highest in polysomes from 1-week tissue. The polysomes contain both acid and alkaline RNase, but the alkaline RNase is the latent form, manifested by the addition of p-chloromercuribenzoate (pCMB). The high RNase activity of granulation tissue renders the analysis of polysomal patterns and functions of the polysomes difficult. In the post-polysomal supernatant of granulation tissue the RNase activity is highest in 2-4 week old tissue; it is maximal at pH 7-8 and only slightly influenced by pCMB.

The feedback effect of granulation‐tissue extract on the subcellular level: the degradation of ribosomes

“…Relevant biological factors have been found to inhibit protein synthesis in experimental granulation tissue glycoproteins (Randoux et al 1976, Jimenez et al 1979, Maquart et al 1980, Schilz & Ward 1980, Kulonen & Potila 1980b). The effect of extracts of mononuclear cells (Jimenez et al 1980) presumably is also due to ribonuclease, which is interesting in this context (Aho & Kulonen 1979). We have developed a hypothesis on the mechanism of silicosis based on the metabolism of KNA (Aho & Kulonen 1977, Kuloncn et i l l .…”