Tissue-specific expression of inducible and constitutive Hsp70 isoforms in the western painted turtle

Abstract

Expression of Hsp73 and Hsp72 in four tissues of the naturally anoxia-tolerant western painted turtle (Chrysemys picta) was investigated in response to a 24 h forced dive and following 1 h recovery. Of the tissues examined, brain and liver displayed approximately threefold and sevenfold higher basal Hsp73 expression than heart and skeletal muscle. Basal Hsp72 expression was relatively low in all tissues examined. After the 24 h forced dive and 1 h recovery, Hsp73 expression did not differ significantly from basal expression with the exception of liver, where expression decreased significantly after 1 h recovery. Hsp72 expression was unchanged in liver following a 24 h dive; however, it increased twofold in brain and threefold in heart and skeletal muscle. Dive-induced Hsp72 expression was found to correlate inversely with basal Hsp73 expression. Following 1 h recovery, Hsp72 expression was significantly elevated in all tissues above levels in dived animals. These data indicate a tissue-specific pattern of Hsp73 and Hsp72 expression in the western painted turtle during both unstressed and stressed conditions.

The Upregulation of Cognate and Inducible Heat Shock Proteins in the Anoxic Turtle Brain

“…Antibodies to Hsp72 and Hsc73 used for this study were previously reported to react specifically with turtle isoforms detecting in each case a single discrete spot by twodimensional gel electrophoresis (Scott et al, 2003). Hsp72 was readily detected in normoxic brain, indicating a high level of baseline expression (Fig.…”

“…However, the current study examined changes in progressive anoxia up to 12 hours, whereas Scott et al (2003) measured changes after 24 hours of forced submergence. Forced submergence might also be an additional stress for the HSP system.…”

Label-free surface-enhanced Raman spectroscopy-linked immunosensor assay (SLISA) for environmental surveillance

“…and HSP70 induction levels in response to toxins are in agreement with previous reports Scott et al 2003 and). …”

Time-dependent expression of heat shock proteins 70 and 90 in tissues of the anoxic western painted turtle

“…Chang et al (2000) provided the first evidence of increased Hsp70 expression in painted turtle myocardium subjected to a 12·h forced dive, but the antibody they used did not distinguish between the constitutive (Hsp73) and inducible (Hsp72) isoform. More recently, Scott et al (2003) reported an increase in the expression of Hsp72 but not Hsp73 in brain, heart and skeletal muscle of western painted turtles force-dived for 24·h at 17°C.…”

“…Since this species undergoes 'translational arrest' during anoxia (Jackson, 2000), the specific upregulation of stress proteins in dived turtles suggests a protective role in long-term anoxic survival (Chang et al, 2000;Scott et al, 2003). However, it is not known whether turtle tissues induce Hsp expression early in a dive period or upregulation of Hsp expression occurs late in a dive as a part of a rescue mechanism triggered near the limit of survival.…”