TY - JOUR
T1 - Eeyarestatin Compounds Selectively Enhance Sec61-Mediated Ca 2+ Leakage from the Endoplasmic Reticulum
AU - Gamayun, Igor
AU - O'Keefe, Sarah
AU - Pick, Tillman
AU - Nguyen, Duy
AU - Klein, Marie Christine
AU - McKibbin, Craig
AU - Piacenti, Michela
AU - Williams, Helen M.
AU - Flitsch, Sabine L.
AU - Whitehead, Roger C.
AU - Swanton, Eileithyia
AU - Helms, Volkhard
AU - High, Stephen
AU - Zimmermann, Richard
AU - Cavalié, Adolfo
N1 - Funding Information:
We thank Roger Y. Tsien, Bernhard Dobberstein, and Per-Olof Berggren for kindly providing us with the calcium sensor D1ER, the HLA class II histocompatibility antigen gamma chain, and the INS-1 cell line, respectively. We acknowledge Dr. Veit Flockerzi (Saarland University) for helpful comments, Dr. Stephan Philipp (Saarland University) for his help in generating the HEK D1ER cell line, and Heidi Löhr and Martin Simon-Thomas (Saarland University) for their excellent technical assistance. This work was supported by the Deutsche Forschungsgemeinschaft (DFG) grants SFB 894 (to R.Z. and A.C.) and IRTG 1830 (to R.Z.), the Biotechnology and Biological Sciences Research Council (BBSRC) Doctoral Training Program Award BB/J014478/1 (S.O.), and the Welcome Trust Investigator Award in Science (2049)57/Z/16/Z ( to S.H.).
Publisher Copyright:
© 2019 The Authors
PY - 2019/4/18
Y1 - 2019/4/18
N2 - Eeyarestatin 1 (ES1) inhibits p97-dependent protein degradation, Sec61-dependent protein translocation into the endoplasmic reticulum (ER), and vesicular transport within the endomembrane system. Here, we show that ES1 impairs Ca 2+ homeostasis by enhancing the Ca 2+ leakage from mammalian ER. A comparison of various ES1 analogs suggested that the 5-nitrofuran (5-NF) ring of ES1 is crucial for this effect. Accordingly, the analog ES24, which conserves the 5-NF domain of ES1, selectively inhibited protein translocation into the ER, displayed the highest potency on ER Ca 2+ leakage of ES1 analogs studied and induced Ca 2+ -dependent cell death. Using small interfering RNA-mediated knockdown of Sec61α, we identified Sec61 complexes as the targets that mediate the gain of Ca 2+ leakage induced by ES1 and ES24. By interacting with the lateral gate of Sec61α, ES1 and ES24 likely capture Sec61 complexes in a Ca 2+ -permeable, open state, in which Sec61 complexes allow Ca 2+ leakage but are translocation incompetent.
AB - Eeyarestatin 1 (ES1) inhibits p97-dependent protein degradation, Sec61-dependent protein translocation into the endoplasmic reticulum (ER), and vesicular transport within the endomembrane system. Here, we show that ES1 impairs Ca 2+ homeostasis by enhancing the Ca 2+ leakage from mammalian ER. A comparison of various ES1 analogs suggested that the 5-nitrofuran (5-NF) ring of ES1 is crucial for this effect. Accordingly, the analog ES24, which conserves the 5-NF domain of ES1, selectively inhibited protein translocation into the ER, displayed the highest potency on ER Ca 2+ leakage of ES1 analogs studied and induced Ca 2+ -dependent cell death. Using small interfering RNA-mediated knockdown of Sec61α, we identified Sec61 complexes as the targets that mediate the gain of Ca 2+ leakage induced by ES1 and ES24. By interacting with the lateral gate of Sec61α, ES1 and ES24 likely capture Sec61 complexes in a Ca 2+ -permeable, open state, in which Sec61 complexes allow Ca 2+ leakage but are translocation incompetent.
KW - calcium homeostasis
KW - calcium-dependent cytotoxicity
KW - eeyarestatin
KW - endoplasmic reticulum
KW - endoplasmic reticulum calcium content
KW - endoplasmic reticulum calcium homeostasis
KW - endoplasmic reticulum calcium leakage
KW - Protein translocation and degradation
KW - Sec61 complexes of the endoplasmic reticulum
KW - translocon of endoplasmic reticulum
UR - http://www.scopus.com/inward/record.url?scp=85064176019&partnerID=8YFLogxK
U2 - 10.1016/j.chembiol.2019.01.010
DO - 10.1016/j.chembiol.2019.01.010
M3 - Article
SN - 2451-9456
VL - 26
SP - 571-583.e6
JO - Cell chemical biology
JF - Cell chemical biology
IS - 4
ER -