[Frontiers in Bioscience 9, 110-116, January 1, 2004] 110 OXYGEN SENSORS AND ENERGY SENSORS ACT SYNERGISTICALLY TO ACHIEVE A GRADED ALTERATION IN GENE EXPRESSION: CONSEQUENCES FOR ASSESSING THE LEVEL OF NEUROPROTECTION IN RESPONSE TO STRESSORS

Changes in gene expression are associated with switching to an autoprotected phenotype in response to environmental and physiological stress. Ubiquitous molecular chaperones from the heat shock protein (HSP) superfamily confer neuronal protection that can be blocked by antibodies. Recent research has focused on the interactions between the molecular sensors that affect the increased expression of neuroprotective HSPs above constitutive levels. An examination of the conditions under which the expression of heat shock protein 70 (Hsp70) was up regulated in a hypoxia and anoxia tolerant tropical species, the epaulette shark (Hemiscyllium ocellatum), revealed that up-regulation was dependent on exceeding a stimulus threshold for an oxidative stressor.