RNA METABOLISM IN MOUSE MYELOMA CELLS
1971 年 62 巻 2 号 p. 107-119
詳細
1971 年 62 巻 2 号 p. 107-119
RNA biosynthesis and metabolism in mouse myeloma cells (X5563), producing γ-globulin continuously, was studied in vitro. The characterization of RNA, which was extracted by hot phenol-sodium dodecyl sulfate method with nonionic detergent (Brij 35), was analyzed by means of sucrose density gradient centrifugation and base composition analysis. RNA can be synthesized at constant rate for over 5hr in the cells, under our in vitro suspension culture condition. As the synthesis of 60-80S and 45S RNA is found in the nucleus and inhibited by low concentration of Actinomycin-D, this may be a DNA-dependent RNA synthesis.
Most of 45S RNA in myeloma cells is the precursor of ribosomal RNA. The transition of 45S into 32S proceeds normally in the nucleus, in the presence of Actinomycin-D or cycloheximide, but 18S and 28S RNA are not detected in the cytoplasm. The transfer of RNA from nucleus into cytoplasm may be closely, related to protein synthesis.
