How does the ER signal the nucleus?

When cells are under stress, they signal the nucleus to do something about it. Because of our long-standing work on the secretory system we are particularly interested in the signals that come from unfolded proteins. Such proteins are present as a result of heat stress or certain chemical treatments (eg tunicamycin). Unfolded proteins signal the nucleus to turn on the BiP genes. This is called the Unfolded Protein Response or UPR. This project was started by Nozomu Koizumi and is now carried on by Imma Martinez. We have cloned the Ire gene homologues that encode transmembrane receptor kinases and we are now studying their role in the UPR.

Papers

"Molecular Characterization of Two Arabidopsis Ire1 Homologs,
Endoplasmic Reticulum-Located Transmembrane Protein Kinases" (pdf)

"Genomic analysis of the unfolded protein response in Arabidopsis shows its connection to important cellular processes." (pdf)

Supplemental data for Genomic Analysis of Arabidopsis UPR