A peptide that regulates the metalation of the Arabidopsis ethylene receptor.

Mudge, A.; Mehdi, S.; Michaels, W.; Orosa-Puente, B.; Shen, W.; Sadanandom, A.; Hetherington, F.; Hoppen, C.; Unzen, B.; Groth, G.; Topping, J.F.; Robinson, N.J.; Lindsey, K.

Abstract

Ethylene signalling represents one of the classic hormonal pathways in plants, with diverse roles in development and stress responses. The dimeric ethylene receptor localizes to the endoplasmic reticulum (ER) and contains Cu(I) ions essential for ethylene binding and signalling. As for other vesicular cupro-proteins, the final step of Cu(I) maturation at the ER is undefined. We previously discovered that mutants in the Arabidopsis gene POLARIS (PLS), encoding a 36 amino acid peptide, exhibit constitutive ethylene signalling responses. Here we report a 1:2 thiol-dependent Cu(I):PLS2 complex, with an affinity of 3.79 (±1.5) x1019 M-2. We demonstrate PLS interactions with the transmembrane domain of receptor protein ETR1, the Cu(I) chaperones ATX1 and CCH, and Cu(I)-transporting P1B-type ATPase RAN1 at the ER. Formation of Cu(I)-dependent PLS- cuproprotein adducts at the ER provides a mechanism to modulate the metalation of ETR1, thereby regulating its activity and representing a novel mechanism for plant hormone receptor regulation.

Citation

Mudge, A., Mehdi, S., Michaels, W., Orosa-Puente, B., Shen, W., Sadanandom, A., Hetherington, F., Hoppen, C., Unzen, B., Groth, G., Topping, J., Robinson, N., & Lindsey, K. (online). A peptide that regulates the metalation of the Arabidopsis ethylene receptor. bioRxiv (Preprint Server for Biology), https://doi.org/10.1101/2023.06.15.545071

• Journal Article Type: Article
• Acceptance Date: Jun 16, 2023
• Online Publication Date: Jul 29, 2023
• Deposit Date: Jun 16, 2023
• Publicly Available Date: Sep 4, 2023
• Journal: BioRxiv
• Peer Reviewed: Not Peer Reviewed
• DOI: https://doi.org/10.1101/2023.06.15.545071
• Public URL: https://durham-repository.worktribe.com/output/1171517