タグ「Gene expression」
Author: Mahmoud-Ahmed A.S., Atkinson S., Wong C.S.
Reference: Radiat Res. ― 2006. ― Vol. 165, № 2. ― P. 142–154.
Keywords: gene expression, RNA, mice
Abstract: Acute changes in the gene expression profile in mouse brain after exposure to ionizing radiation were studied using microarray analysis. RNA was isolated at 0.25, 1, 5 and 24 h after exposure to 20 Gy and at 5 h after exposure of the whole brain of adult mice to 2 or 10 Gy. RNA was hybridized onto 15K cDNA microarrays, and data were analyzed using GeneSpring and Significant Analysis of Microarray. Radiation modulated the expression of 128, 334, 325 and 155 genes and ESTs at 0.25, 1, 5 and 24 h after 20 Gy and 60 and 168 at 5 h after 2 and 10 Gy, respectively. The expression profiles showed dose- and time-dependent changes in both expression levels and numbers of differentially modulated genes and ESTs. Seventy-eight genes were modulated at two or more times. Differentially modulated genes were associated with 12 different classes of molecular function and 24 different biological pathways and showed time- and dose-dependent changes. The change in expression of four genes (Jak3, Dffb, Nsep1 and Terf1) after irradiation was validated using quantitative real-time PCR. Up-regulation of Jak3 was observed in another mouse strain. In mouse brain, there was an increase of Jak3 immunoreactivity after irradiation. In conclusion, changes in the gene profile in the brain after irradiation are complex and are dependent on time and dose, and genes with diverse functions and pathways are modulated.
URL: http://www.ncbi.nlm.nih.gov/pubmed/16435913
Author: E. Yin, D.O. Nelson, M.A. Coleman et al.
Reference: Int. J. Radiat. Biol. ― 2003. ― Vol. 79, № 10. ― P. 759–775.
Keywords: gene expression, metabolic function, DNA
Abstract: PURPOSE: To characterize the cellular functions associated with the altered transcript profiles of mouse brain exposed to low-dose in vivo gamma-irradiation.
MATERIALS AND METHODS: Cerebral RNA was isolated at 30 min and 4 h after whole-body irradiation at 0.1 or 2 Gy, hybridized to random oligonucleotide arrays, and evaluated for time and dose-response patterns by multifactorial analyses.
RESULTS: Brain irradiation modulated the expression patterns of 1574 genes, of which 855 showed more than 1.5-fold variation. about 30% of genes showed dose-dependent variations, including genes exclusively affected by 0.1 Gy. About 60% of genes showed time-dependent variation with more genes affected at 30 min than at 4 h. Early changes involved signal transduction, ion regulation and synaptic signalling. Later changes involved metabolic functions including myelin and protein synthesis. Low-dose radiation also modulated the expression of genes involved in stress response, cell-cycle control and DNA synthesis/repair.
CONCLUSIONS: Doses of 0.1 Gy induced changes in gene expression that were qualitatively different from those at 2 Gy. The findings suggest that low-dose irradiation of the brain induces the expression of genes involved in protective and reparative functions, while down-modulating genes involved in neural signalling activity.
URL: http://www.ncbi.nlm.nih.gov/pubmed/20399419
Title: Fetal cell carcinogenesis of the thyroid: Theory and practice
Author: Takano, Toru
Reference: Seminars in Cancer Biology, 17 (3), p.233-240, Jun 2007
doi: 10.1016/j.semcancer.2006.02.001
Keywords: Neoplasms; Stem cells; Thyroid gland; Gene expression; Fetal cell research
Abstract: …dominant in the fetal thyroid. This fact suggests…estrogen may help the fetal thyroid to increase its volume…hypothesis. First, in the Chernobyl accident, radioactive…the ability to induce thyroid cancer in adults, induced papillary…
URL: http://www.sciencedirect.com/science/article/pii/S1044579X06000228
