Inhibition of Protein Synthesis in Developing Mouse Brain after Fission Neutron Irradiation in Utero

Previous investigations showed that when pregnant mice were exposed to a single whole-body dose of 0.5 Gy fission neutrons on Day 17 ± 2 of gestation [H. H. Vogel, Jr. and S. Antal, Radiat. Res. 98, 52-64 (1984)] about 40% of the newborn mice died and the body and brain weights of surviving animals...

Full description

Saved in:

Bibliographic Details
Published in:	Radiation research Vol. 103; no. 1; pp. 34 - 45
Main Authors:	Fónagy, Anna, Antal, Sára, Holland, József, Kőrösi, László, Hidvégi, Egon J.
Format:	Journal Article
Language:	English
Published:	Oak Brook, Il Academic Press, Inc 01-07-1985 Radiation Research Society
Subjects:	Amino acids Amino Acids - metabolism Animals Biological and medical sciences Biological effects of radiation Body Weight - radiation effects Brain Brain - growth & development Brain - radiation effects Chromosomal Proteins, Non-Histone - metabolism DNA Replication - radiation effects Female Fundamental and applied biological sciences. Psychology Histones Histones - biosynthesis Ionizing radiations Irradiation Liver Liver - metabolism Male Mice Mice, Inbred C57BL Mice, Inbred DBA Neutron irradiation Neutrons Nuclear proteins Organ Size - radiation effects Pregnancy Pregnancy Proteins - biosynthesis Prenatal Exposure Delayed Effects Protein Biosynthesis Protein synthesis RNA RNA - biosynthesis RNA, Transfer, Amino Acyl - metabolism Space life sciences Tissues, organs and organisms biophysics Whole-Body Irradiation Embryonic development Vertebrata Ionizing radiation Mammalia Mouse Protein synthesis Aminoacid Rodentia Neutrons Inhibition In utero
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Previous investigations showed that when pregnant mice were exposed to a single whole-body dose of 0.5 Gy fission neutrons on Day 17 ± 2 of gestation [H. H. Vogel, Jr. and S. Antal, Radiat. Res. 98, 52-64 (1984)] about 40% of the newborn mice died and the body and brain weights of surviving animals decreased by 30-35%. Decreases of body and brain weights were most prominent by the third week after birth, but the content of nucleic acids related to wet weight did not change in liver and brain upon irradiation [S. Antal, A. Fónagy, Z. Fölöp, E. J. Hidvégi, and H. H. Vogel, Jr. Int. J. Radiat. Biol. 46, 425-433 (1984)]. Studies presented in this paper show that after a single whole-body dose of 0.5 Gy neutron irradiation on Day 18 of pregnancy protein synthesis decreased in liver and brain of 3-week-old mice irradiated in utero. Incorporation of labeled amino acids in vivo into acid soluble nuclear proteins decreased by 15% in liver and by 40% in brain. It was significantly reduced into brain histones and certain brain nonhistone proteins (separated by two-dimensional electrophoresis). The amount of H1 and H4 brain histones decreased as well. Investigations with isolated protein synthesizing systems proved that the peptide bond formation was not impaired by irradiation. The aminoacylation of transfer-RNA, however, decreased in both liver and brain by 26-34 and 34-41%, respectively. Comparing the aminoacylation capacities in the two unirradiated organs, a much lower (about one-third) capacity was found in brain than in liver. Moreover, this low aminoacylation capacity of brain decreased further by about 40% after neutron irradiation. These results suggest that in the developing irradiated brain the reduced capacity of aminoacylation of transfer-RNA might be rate limiting for the efficiency of protein synthesis.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0033-7587 1938-5404
DOI:	10.2307/3576669