Transition metal transporting P-type ATPases : terminal metal-binding domains serve as sensors for autoinhibitory tails
(2024) In FEBS Journal- Abstract
Copper is an essential micronutrient and yet is highly toxic to cells at elevated concentrations. P1B-ATPase proteins are critical for this regulation, providing active extrusion across cellular membranes. One unique molecular adaptation of P1B-ATPases compared to other P-type ATPases is the presence of metal-binding domains (MBDs) at the cytosolic termini, which however are poorly characterized with an elusive mechanistic role. Here we present the MBD architecture in metal-free and metal-bound forms of the archetype Cu+-specific P1B-ATPase LpCopA, determined using NMR. The MBD is composed of a flexible tail and a structured core with a metal ion binding site defined by three sulfur atoms, one... (More)
Copper is an essential micronutrient and yet is highly toxic to cells at elevated concentrations. P1B-ATPase proteins are critical for this regulation, providing active extrusion across cellular membranes. One unique molecular adaptation of P1B-ATPases compared to other P-type ATPases is the presence of metal-binding domains (MBDs) at the cytosolic termini, which however are poorly characterized with an elusive mechanistic role. Here we present the MBD architecture in metal-free and metal-bound forms of the archetype Cu+-specific P1B-ATPase LpCopA, determined using NMR. The MBD is composed of a flexible tail and a structured core with a metal ion binding site defined by three sulfur atoms, one of which is pertinent to the so-called CXXC motif. Furthermore, we demonstrate that the MBD rather than being involved in ion delivery likely serves a regulatory role, which is dependent on the classical P-type ATPase E1-E2 transport mechanism. Specifically, the flexible tail appears responsible for autoinhibition while the metal-binding core is used for copper sensing. This model is validated by a conformation-sensitive and MBD-targeting nanobody that can structurally and functionally replace the flexible tail. We propose that autoinhibition of Cu+-ATPases occurs at low copper conditions via MBD-mediated interference with the soluble domains of the ATPase core and that metal transport is enabled when copper levels rise, through metal-induced dissociation of the MBD. This allows P1B-ATPase ‘vacuum cleaners’ to tune their own activity, balancing the levels of critical micronutrients in the cells.
(Less)
- author
- organization
- publishing date
- 2024
- type
- Contribution to journal
- publication status
- epub
- subject
- keywords
- autoinhibition, copper transport, metal-binding domains, P-type ATPases, regulation
- in
- FEBS Journal
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- pmid:39609265
- scopus:85210524696
- ISSN
- 1742-464X
- DOI
- 10.1111/febs.17330
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: © 2024 The Author(s). The FEBS Journal published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.
- id
- 51bb4b8b-268e-4c05-b8cc-e145a09c298f
- date added to LUP
- 2025-01-22 13:22:25
- date last changed
- 2025-07-10 03:02:34
@article{51bb4b8b-268e-4c05-b8cc-e145a09c298f,
abstract = {{<p>Copper is an essential micronutrient and yet is highly toxic to cells at elevated concentrations. P<sub>1B</sub>-ATPase proteins are critical for this regulation, providing active extrusion across cellular membranes. One unique molecular adaptation of P<sub>1B</sub>-ATPases compared to other P-type ATPases is the presence of metal-binding domains (MBDs) at the cytosolic termini, which however are poorly characterized with an elusive mechanistic role. Here we present the MBD architecture in metal-free and metal-bound forms of the archetype Cu<sup>+</sup>-specific P<sub>1B</sub>-ATPase LpCopA, determined using NMR. The MBD is composed of a flexible tail and a structured core with a metal ion binding site defined by three sulfur atoms, one of which is pertinent to the so-called CXXC motif. Furthermore, we demonstrate that the MBD rather than being involved in ion delivery likely serves a regulatory role, which is dependent on the classical P-type ATPase E1-E2 transport mechanism. Specifically, the flexible tail appears responsible for autoinhibition while the metal-binding core is used for copper sensing. This model is validated by a conformation-sensitive and MBD-targeting nanobody that can structurally and functionally replace the flexible tail. We propose that autoinhibition of Cu<sup>+</sup>-ATPases occurs at low copper conditions via MBD-mediated interference with the soluble domains of the ATPase core and that metal transport is enabled when copper levels rise, through metal-induced dissociation of the MBD. This allows P<sub>1B</sub>-ATPase ‘vacuum cleaners’ to tune their own activity, balancing the levels of critical micronutrients in the cells.</p>}},
author = {{Hu, Qiaoxia and Sitsel, Oleg and Bågenholm, Viktoria and Grønberg, Christina and Lyu, Pin and Pii Svane, Anna Sigrid and Andersen, Kasper Røjkjær and Laursen, Nick Stub and Meloni, Gabriele and Nissen, Poul and Juhl, Dennis W. and Nielsen, Jakob Toudahl and Nielsen, Niels Chr and Gourdon, Pontus}},
issn = {{1742-464X}},
keywords = {{autoinhibition; copper transport; metal-binding domains; P-type ATPases; regulation}},
language = {{eng}},
publisher = {{John Wiley & Sons Inc.}},
series = {{FEBS Journal}},
title = {{Transition metal transporting P-type ATPases : terminal metal-binding domains serve as sensors for autoinhibitory tails}},
url = {{http://dx.doi.org/10.1111/febs.17330}},
doi = {{10.1111/febs.17330}},
year = {{2024}},
}