18 S rRNA degradation is not accompanied by altered rRNA transport at early times following irradiation of HeLa cells

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Radiation Research; (USA)

DOI:https://doi.org/10.2307/3577565· OSTI ID:7025394

Fuchs, P; Krolak, J M; McClain, D; Minton, K W ^[1]

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1. Israel Institute for Biological Research, Ness-Ziona (Israel)

The effect of ionizing radiation ({sup 137}Cs) on processing and transport of ribosomal RNA (rRNA) was studied by pulse-labeling HeLa S3 cells with ({sup 3}H)uridine immediately prior to irradiation. This approach permits kinetic analysis of processing of 45 S rRNA (radiolabeled predominantly prior to irradiation) into its 28 S and 18 S rRNA daughter species following irradiation. By this technique, we have recently demonstrated an increase in the normal 28 S:18 S rRNA stoichiometric ratio of 1:1 to as high as 1.6:1 during the interval 5 to 20 h following irradiation of HeLa cells at greater than or equal to 7.5 Gy. Alterations in 28 S:18 S ratio were evaluated in greater detail at early times following irradiation, up to 2 h. The 28 S:18 S ratio was found to be maximal at 1 h after radiation, at about 2:1, following 5 or 10 Gy. Using a method for rapid separation of nucleus from cytoplasm, transport of rRNA from nucleus to cytoplasm was also evaluated during this period. Despite an increase in the rate of 45 S rRNA processing, as well as an increased 28 S:18 S ratio, no alterations in transport from nucleus to cytoplasm were detected. This lack of transport alteration suggests that accumulation of excess 28 S rRNA is restricted to the nucleus, where it may represent an early step in the process of radiation-induced cell killing.

• OSTI ID: 7025394
• Journal Information: Radiation Research; (USA), Journal Name: Radiation Research; (USA) Vol. 121:1; ISSN 0033-7587; ISSN RAREA
• Country of Publication: United States
• Language: English

Related Subjects

550901 -- Pathology-- Tracer Techniques
560120* -- Radiation Effects on Biochemicals
Cells
& Tissue Culture
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALI METAL ISOTOPES
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CELL CONSTITUENTS
CELL KILLING
CELL NUCLEI
CESIUM 137
CESIUM ISOTOPES
CYTOPLASM
ELECTROMAGNETIC RADIATION
GAMMA RADIATION
HELA CELLS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
IN VITRO
IONIZING RADIATIONS
ISOTOPE APPLICATIONS
ISOTOPES
NUCLEI
NUCLEOSIDES
NUCLEOTIDES
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIMIDINES
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
RIBOSIDES
TRACER TECHNIQUES
TRITIUM COMPOUNDS
URACILS
URIDINE
YEARS LIVING RADIOISOTOPES