Decreased temperature as a signal for regulation of heat shock protein expression in anoxic brain and heart: focus on 'Expression of heat shock proteins in anoxic crucian carp (Carassius carassius): support for cold as a preparatory cue for anoxia'.

摘要

The paper by stenslokken et al. (16) is an important investigation that examines the levels of expression of heat shock proteins (HSPs) in crucian carp (Carassius carassius) brain based on the prediction that there would be increases in expression of heat shock proteins in anoxia and that these alterations in expression would be of smaller magnitude at lower temperatures (8degC compared with 13degC). The crucian carp is a key model of anoxia tolerance as it survives in total oxygen deprivation for durations of days at room temperature to months at lower temperatures. By employing a real-time PCR analysis, Stensl0kken et al. (16) demonstrated that levels of mRNAs for several heat shock proteins HSP70a, HSP70b, HSC70, HSP90, and HSP30 changed in anoxia with a dramatic increase in HSP70a mRNA expression in day 7 anoxic brains and hearts at 13degC but not at 8degC. Under normoxic conditions, a 7- and 11-fold higher HSP70a expression was found at 8degC in brain and heart, respectively, by comparison to 13degC. In anoxia, the differences in HSP70a expression at 8degC by comparison to 13degC were minimal (only 1.1 for brain and 1.9-fold for heart). These observations indicate that cold temperatures may play a preconditioning role in the brain and heart of the crucian carp to elicit tolerance for upcoming anoxia.