HuR function and translational state analysis following global brain ischemia and reperfusion

Transl Stroke Res. 2013 Dec;4(6):589-603. doi: 10.1007/s12975-013-0273-2. Epub 2013 Aug 2.

Abstract

Prolonged translation arrest in post-ischemic hippocampal CA1 pyramidal neurons precludes translation of induced stress genes and directly correlates with cell death. We evaluated the regulation of mRNAs containing adenine- and uridine-rich elements (ARE) by assessing HuR protein and hsp70 mRNA nuclear translocation, HuR polysome binding, and translation state analysis of CA1 and CA3 at 8 h of reperfusion after 10 min of global cerebral ischemia. There was no difference between CA1 and CA3 at 8 h of reperfusion in nuclear or cytoplasmic HuR protein or hsp70 mRNA, or HuR polysome association, suggesting that neither mechanism contributed to post-ischemic outcome. Translation state analysis revealed that 28 and 58 % of unique mRNAs significantly different between 8hR and NIC, in CA3 and CA1, respectively, were not polysome-bound. There was significantly greater diversity of polysome-bound mRNAs in reperfused CA3 compared to CA1, and in both regions, ARE-containing mRNAs accounted for 4-5 % of the total. These data indicate that posttranscriptional ARE-containing mRNA regulation occurs in reperfused neurons and contributes to post-ischemic outcome. Understanding the differential responses of vulnerable and resistant neurons to ischemia will contribute to the development of effective neuroprotective therapies.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenine / metabolism
  • Animals
  • Blotting, Western
  • Brain Ischemia / metabolism*
  • CA1 Region, Hippocampal / metabolism*
  • CA3 Region, Hippocampal / metabolism*
  • ELAV Proteins / metabolism
  • HSP70 Heat-Shock Proteins / metabolism
  • Male
  • Neurons / metabolism*
  • RNA, Messenger / metabolism*
  • Rats
  • Rats, Long-Evans
  • Reperfusion Injury / metabolism*
  • Uridine / metabolism

Substances

  • ELAV Proteins
  • HSP70 Heat-Shock Proteins
  • RNA, Messenger
  • Adenine
  • Uridine