Profiling the Dual Enzymatic Activities of the Serine/Threonine Kinase IRE1α

  • Hannah C. Feldman
  • Dustin J. MalyEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1513)


There is an allosteric relationship between the kinase and RNase domains of the ER stress sensor IRE1α. This relationship has been exploited to develop ATP-competitive inhibitors that are able to divergently modulate the RNase activity of IRE1α through its kinase domain. Here, we describe a series of biochemical methods for profiling the dual enzymatic activities of IRE1α. These methods can be used to ascertain how ATP-competitive inhibitors affect the kinase activity of IRE1α and for determining whether these ligands allosterically activate or inactivate RNase activity.

Key words

Protein kinase Endoribonuclease Allostery IC50 Inhibitor RNase 


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Copyright information

© Springer Science+Business Media New York 2017

Authors and Affiliations

  1. 1.Department of ChemistryUniversity of WashingtonSeattleUSA
  2. 2.Department of BiochemistryUniversity of WashingtonSeattleUSA

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