Abstract |
In this study, we examined the effect of concurrent low concentrations of sodium arsenite and mild heat shock temperatures on hsp30 and hsp70 gene expression in Xenopus A6 kidney epithelial cells. RNA blot hybridization and immunoblot analysis revealed that exposure of A6 cells to 1-10 microM sodium arsenite at a mild heat shock temperature of 30 degrees C enhanced hsp30 and hsp70 gene expression to a much greater extent than found with either stress individually. In cells treated simultaneously with 10 microM sodium arsenite and different heat shock temperatures, enhanced accumulation of HSP30 and HSP70 protein was first detected at 26 degrees C with larger responses at 28 and 30 degrees C. HSF1 activity was involved in combined stress-induced hsp gene expression since the HSF1 activation inhibitor, KNK437, inhibited HSP30 and HSP70 accumulation. Immunocytochemical analysis revealed that HSP30 was present in a granular pattern primarily in the cytoplasm in cells treated simultaneously with both stresses. Finally, prior exposure of A6 cells to concurrent sodium arsenite (10 microM) and heat shock (30 degrees C) treatment conferred thermotolerance since it protected them against a subsequent thermal challenge (37 degrees C). Acquired thermotolerance was not observed with cells treated with the two mild stresses individually.
|
Authors | Jordan T F Young, Julie Gauley, John J Heikkila |
Journal | Comparative biochemistry and physiology. Part A, Molecular & integrative physiology
(Comp Biochem Physiol A Mol Integr Physiol)
Vol. 153
Issue 4
Pg. 417-24
(Aug 2009)
ISSN: 1531-4332 [Electronic] United States |
PMID | 19358893
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
|
Chemical References |
- Arsenites
- HSP30 Heat-Shock Proteins
- HSP70 Heat-Shock Proteins
- Sodium Compounds
- sodium arsenite
|
Topics |
- Adaptation, Physiological
- Animals
- Arsenites
(pharmacology)
- Blotting, Northern
- Epithelial Cells
(drug effects, metabolism)
- HSP30 Heat-Shock Proteins
(genetics)
- HSP70 Heat-Shock Proteins
(genetics)
- Hot Temperature
- Immunohistochemistry
- Kidney
(cytology, drug effects, metabolism, physiology)
- Microscopy, Confocal
- Sodium Compounds
(pharmacology)
- Xenopus
|