Uptake of Transfer Ribonucleic Acid by Normal and Leukemic Cells*
AUTOR(ES)
Herrera, Flor
RESUMO
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 with E. coli aminoacyl-tRNA synthetases; (b) methylation with leukemic cell tRNA-methylases, and (c) demonstrating 14C-labeled 4S RNA in the cytoplasmic fraction of the leukemic cells after the addition of E. coli [14C]tRNA. The results demonstrate that tRNA can enter mammalian cells and suggest that an energy independent, carrier-mediated, mechanism may be operative.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=283451Documentos Relacionados
- COMPLEX MITOCHONDRIAL DNA IN LEUKEMIC AND NORMAL HUMAN MYELOID CELLS*
- RIBONUCLEIC ACID-INDUCED CHANGES IN MAMMALIAN CELLS*
- AN INFECTIOUS RIBONUCLEIC ACID DERIVED FROM INFLUENZA-INFECTED CELLS*
- Transfer Ribonucleic Acid Nucleotidyltransferase and Transfer Ribonucleic Acid in Sendai Virions
- Metabolism of Separated Leaf Cells: II. Uptake and Incorporation of Protein and Ribonucleic Acid Precursors by Tobacco Cells 1