Induction of Apg-1, a member of the heat shock protein 110 family, following transient forebrain ischemia in the rat brain.

Abstract

Apg-1 (Osp94) and apg-2 belong to the heat shock protein (hsp) 110 family. In mouse somatic cells the apg-1 and hsp105/110 transcripts are inducible by a 32 degrees C to 39 degrees C heat shock, while apg-2 is not heat-inducible. Since ischemia is known to induce expression of hsp70, its effect on expression of apg-1 was assessed by using the 20-min forebrain ischemia model of the rat. In the cerebral cortex, Northern blot analysis and in situ hybridization histochemistry demonstrated an increased expression in neuronal cells of apg-1 transcripts 3 h after the onset of reperfusion, with a peak at 12 h, followed by a decline. In the hippocampus, the level was increased at 3 h, remained constant until 24 h, and then declined. Transcript levels of apg-2 as well as hsp 105 were also increased under the present conditions, indicating that the expression of apg-2 was differentially regulated in response to heat and ischemic stresses. The induction kinetics of hsp 105, but neither apg-2 nor hsp 70, were identical to those of apg-1. These results demonstrated that brain ischemia/reperfusion induced expression of each member of the hsp 110 family, although the regulatory mechanisms may not be the same. They also suggest a significant role of apg-1 in both the ischemic- and heat-stress responses and in the normal functioning of the non-stressed neuronal cells.

• Authors: J H Xue, H Fukuyama, K Nonoguchi, Y Kaneko, T Kido, M Fukumoto, Y Fujibayashi, K Itoh, J Fujita
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 247 Issue 3 Pg. 796-801 (Jun 29 1998) ISSN: 0006-291X [Print] United States
• PMID: 9647773 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• HSP70 Heat-Shock Proteins
• Heat-Shock Proteins
• Hspa4l protein, rat
• RNA, Messenger

Topics

• Animals
• Brain (metabolism)
• Brain Ischemia (physiopathology)
• Disease Models, Animal
• Gene Expression Regulation (genetics)
• HSP70 Heat-Shock Proteins
• Heat-Shock Proteins (metabolism)
• In Situ Hybridization
• Male
• RNA, Messenger (metabolism)
• Rats
• Rats, Wistar
• Temperature