Exploring the IRE1 interactome: From canonical signaling functions to unexpected roles

J Biol Chem. 2024 Apr;300(4):107169. doi: 10.1016/j.jbc.2024.107169. Epub 2024 Mar 15.

Abstract

The unfolded protein response is a mechanism aiming at restoring endoplasmic reticulum (ER) homeostasis and is likely involved in other adaptive pathways. The unfolded protein response is transduced by three proteins acting as sensors and triggering downstream signaling pathways. Among them, inositol-requiring enzyme 1 alpha (IRE1α) (referred to as IRE1 hereafter), an endoplasmic reticulum-resident type I transmembrane protein, exerts its function through both kinase and endoribonuclease activities, resulting in both X-box binding protein 1 mRNA splicing and RNA degradation (regulated ire1 dependent decay). An increasing number of studies have reported protein-protein interactions as regulators of these signaling mechanisms, and additionally, driving other noncanonical functions. In this review, we deliver evolutive and structural insights on IRE1 and further describe how this protein interaction network (interactome) regulates IRE1 signaling abilities or mediates other cellular processes through catalytic-independent mechanisms. Moreover, we focus on newly discovered targets of IRE1 kinase activity and discuss potentially novel IRE1 functions based on the nature of the interactome, thereby identifying new fields to explore regarding this protein's biological roles.

Keywords: IRE1; endoplasmic reticulum; interactome; protein homeostasis; signaling; stress; unfolded protein response.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Endoplasmic Reticulum / metabolism
  • Endoribonucleases* / genetics
  • Endoribonucleases* / metabolism
  • Evolution, Molecular
  • Humans
  • Protein Interaction Maps*
  • Protein Serine-Threonine Kinases* / genetics
  • Protein Serine-Threonine Kinases* / metabolism
  • Signal Transduction*
  • Unfolded Protein Response

Substances

  • Endoribonucleases
  • ERN1 protein, human
  • Protein Serine-Threonine Kinases