TY - JOUR
T1 - Alterations in gene expression induced in day-9 mouse embryos exposed to hyperthermia (HS) or 4-hydroperoxycyclophosphamide (4CP)
T2 - Analysis using cDNA microarrays
AU - Mikheeva, Svetlana
AU - Barrier, Marianne
AU - Little, Sally A.
AU - Beyer, Richard
AU - Mikheev, Andrei M.
AU - Kerr, Kathleen
AU - Mirkes, Philip E.
N1 - Funding Information:
This research was supported by NIH grants 2R01ES07026 and 5R01ES08744 to PEM. We thank Sulcheol for technical assistance. The authors also gratefully acknowledge support from the Center for Ecogenetics and Environmental Health (NIH Grant 5P30ES0733) and the FHCRC/UW Toxicogenomics Consortium (U19ES11387).
PY - 2004/6
Y1 - 2004/6
N2 - Teratogen-induced alterations in gene expression play an important role in the genesis of malformations in animals. The recent development of DNA microarrays now offers the opportunity to monitor global changes in gene expression and therefore the potential to obtain significant new information concerning both normal and abnormal development. RNA was isolated from day-9 mouse embryos at 1 and 5 h after exposure to hyperthermia (HS) or 4-hydroperoxycyclophosphamide (4CP) and compared to RNA isolated from concurrent controls using mouse cDNA microarrays. Cy5/Cy3 intensity data were extracted using Spot-on Image software and then normalized using the statistical software program R/maanova. Differentially expressed genes were identified using a linear mixed-effects model and p values derived from t-test statistics. Approximately 9000 genes show statistically significant alterations in expression in day-9 mouse embryos exposed to HS or 4CP. HS and 4CP also induce alterations in the expression of distinct sets of genes, e.g., DNA replication/repair, cell cycle, signal transduction, and transcription-related genes. As expected, a variety of heat shock genes are upregulated by HS but not 4CP. Among genes whose expression is altered by both HS and 4CP, cluster analysis identified three p53 target genes (Cyclin G1, Gtse1, and Mdm2), and follow up studies confirmed that p53 is activated in embryos exposed to these two teratogens. In addition, cluster analyses also revealed that HS but not 4CP induces the downregulation of genes encoding key enzymes in the cholesterol biosynthesis pathway. Thus, our microarray data have identified one potentially important pathway (p53) common to both HS- and 4CP-induced teratogenesis and another pathway (cholesterol biosynthesis) potentially important, but specific to HS-induced teratogenesis.
AB - Teratogen-induced alterations in gene expression play an important role in the genesis of malformations in animals. The recent development of DNA microarrays now offers the opportunity to monitor global changes in gene expression and therefore the potential to obtain significant new information concerning both normal and abnormal development. RNA was isolated from day-9 mouse embryos at 1 and 5 h after exposure to hyperthermia (HS) or 4-hydroperoxycyclophosphamide (4CP) and compared to RNA isolated from concurrent controls using mouse cDNA microarrays. Cy5/Cy3 intensity data were extracted using Spot-on Image software and then normalized using the statistical software program R/maanova. Differentially expressed genes were identified using a linear mixed-effects model and p values derived from t-test statistics. Approximately 9000 genes show statistically significant alterations in expression in day-9 mouse embryos exposed to HS or 4CP. HS and 4CP also induce alterations in the expression of distinct sets of genes, e.g., DNA replication/repair, cell cycle, signal transduction, and transcription-related genes. As expected, a variety of heat shock genes are upregulated by HS but not 4CP. Among genes whose expression is altered by both HS and 4CP, cluster analysis identified three p53 target genes (Cyclin G1, Gtse1, and Mdm2), and follow up studies confirmed that p53 is activated in embryos exposed to these two teratogens. In addition, cluster analyses also revealed that HS but not 4CP induces the downregulation of genes encoding key enzymes in the cholesterol biosynthesis pathway. Thus, our microarray data have identified one potentially important pathway (p53) common to both HS- and 4CP-induced teratogenesis and another pathway (cholesterol biosynthesis) potentially important, but specific to HS-induced teratogenesis.
KW - 4-hydroperoxycyclophosphamide
KW - Day-9 mouse embryos
KW - Gene expression profiling
KW - Hyperthermia
KW - cDNA microarrays
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U2 - 10.1093/toxsci/kfh080
DO - 10.1093/toxsci/kfh080
M3 - Article
C2 - 14976350
AN - SCOPUS:2942744822
SN - 1096-6080
VL - 79
SP - 345
EP - 359
JO - Toxicological Sciences
JF - Toxicological Sciences
IS - 2
ER -