Open AccessUptake of Transfer Ribonucleic Acid by Normal and Leukemic Cells
Author(s) -
Flor Herrera,
Richard H. Adamson,
Robert C. Gallo
Publication year - 1970
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.67.4.1943
Subject(s) - transfer rna , biochemistry , escherichia coli , rna , ribonuclease , biology , cell , microbiology and biotechnology , cell culture , cytoplasm , chemistry , genetics , gene
Uptake of tRNA (Escherichia coli ) was demonstrated in the murine leukemia, L1210 and in a human lymphoblast (NC-37) cell lines. In both cell lines, uptake of tRNA was rapid, reaching a maximum within 45 sec, and was linear with concentration up to about 50 μg/ml. This uptake of exogenous tRNA apparently was not due to altered membrane permeability or impaired cell viability, nor to ribonuclease degradation of the macromolecule. Furthermore, about 20% of the tRNA taken up by the cells remains functional and apparently intact. This was demonstrated by: (a ) acylation withE. coli aminoacyl-tRNA synthetases; (b ) methylation with leukemic cell tRNA-methylases, and (c ) demonstrating14 C-labeled 4S RNA in the cytoplasmic fraction of the leukemic cells after the addition ofE. coli [14 C]tRNA. The results demonstrate that tRNA can enter mammalian cells and suggest that an energy independent, carrier-mediated, mechanism may be operative.