Radiation-induced gene expression in the nematode Caenorhabditis elegans.
We used the nematode C. elegans to characterize the genotoxic and cytotoxic effects of ionizing radiation in a simple animal model emphasizing the unique effects of charged particle radiation. Here we demonstrate by RT-PCR differential display and whole genome microarray hybridization experiments that gamma rays, accelerated protons and iron ions at the same physical dose lead to unique transcription profiles. 599 of 17871 genes analyzed (3.4%) showed differential expression 3 hrs after exposure to 3 Gy of radiation. 193 were up-regulated, 406 were down-regulated and 90% were affected only by a single species of radiation. A novel statistical clustering technique identified the regulatory relationships between the radiation-modulated genes and showed that genes affected by each radiation species were associated with unique regulatory clusters. This suggests that independent homeostatic mechanisms are activated in response to radiation exposure as a function of track structure or ionization density.
Nelson
Gregory A
GA
Loma Linda University Radiobiology Program, 11175 Campus St., Chan Shun Pavilion A1010 Loma Linda, California 92354, USA. gnelson@dominion.llumc.edu
Jones
Tamako A
TA
Chesnut
Aaron
A
Smith
Anna L
AL
D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics*; D046508:Culture Techniques; D005720:Gamma Rays; D015870:Gene Expression / Q000528:radiation effects*; D020869:Gene Expression Profiling; D007501:Iron; D018499:Linear Energy Transfer; D020411:Oligonucleotide Array Sequence Analysis; D010315:Particle Accelerators; D014158:Transcription, Genetic / Q000528:radiation effects
D007501:Iron