1
|
Sysoeva TA. Assessing heterogeneity in oligomeric AAA+ machines. Cell Mol Life Sci 2017; 74:1001-1018. [PMID: 27669691 PMCID: PMC11107579 DOI: 10.1007/s00018-016-2374-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 09/13/2016] [Accepted: 09/19/2016] [Indexed: 10/20/2022]
Abstract
ATPases Associated with various cellular Activities (AAA+ ATPases) are molecular motors that use the energy of ATP binding and hydrolysis to remodel their target macromolecules. The majority of these ATPases form ring-shaped hexamers in which the active sites are located at the interfaces between neighboring subunits. Structural changes initiate in an active site and propagate to distant motor parts that interface and reshape the target macromolecules, thereby performing mechanical work. During the functioning cycle, the AAA+ motor transits through multiple distinct states. Ring architecture and placement of the catalytic sites at the intersubunit interfaces allow for a unique level of coordination among subunits of the motor. This in turn results in conformational differences among subunits and overall asymmetry of the motor ring as it functions. To date, a large amount of structural information has been gathered for different AAA+ motors, but even for the most characterized of them only a few structural states are known and the full mechanistic cycle cannot be yet reconstructed. Therefore, the first part of this work will provide a broad overview of what arrangements of AAA+ subunits have been structurally observed focusing on diversity of ATPase oligomeric ensembles and heterogeneity within the ensembles. The second part of this review will concentrate on methods that assess structural and functional heterogeneity among subunits of AAA+ motors, thus bringing us closer to understanding the mechanism of these fascinating molecular motors.
Collapse
Affiliation(s)
- Tatyana A Sysoeva
- Department of Biomedical Engineering, Duke University, Durham, NC, 27708, USA.
| |
Collapse
|
2
|
Nähse V, Christ L, Stenmark H, Campsteijn C. The Abscission Checkpoint: Making It to the Final Cut. Trends Cell Biol 2016; 27:1-11. [PMID: 27810282 DOI: 10.1016/j.tcb.2016.10.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Revised: 10/08/2016] [Accepted: 10/11/2016] [Indexed: 12/11/2022]
Abstract
Cytokinesis is the final stage of cell division and is concluded by abscission of the intercellular bridge to physically separate the daughter cells. Timing of cytokinetic abscission is monitored by a molecular machinery termed the abscission checkpoint. This machinery delays abscission in cells with persistent chromatin in the intercellular bridge. Recent work has also uncovered its response to high membrane tension, nuclear pore defects, and DNA replication stress. Although it is known that the abscission checkpoint depends on persistent activity of the Aurora B protein kinase, we have only recently begun to understand its molecular basis. We propose here a molecular framework for abscission checkpoint signaling and we discuss outstanding questions relating to its function and physiological relevance.
Collapse
Affiliation(s)
- Viola Nähse
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway; Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Liliane Christ
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway; Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Harald Stenmark
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway; Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway; Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Faculty of Medicine, 7491 Trondheim, Norway.
| | - Coen Campsteijn
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Montebello, 0379 Oslo, Norway; Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0379 Oslo, Norway.
| |
Collapse
|
3
|
Akrap I, Thavamani A, Nordheim A. Vps4A-mediated tumor suppression upon exosome modulation? ANNALS OF TRANSLATIONAL MEDICINE 2016; 4:180. [PMID: 27275493 DOI: 10.21037/atm.2016.04.18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Ivana Akrap
- Molecular Biology Unit, Interfaculty Institute of Cell Biology, Tübingen University, Tübingen, Germany
| | - Abhishek Thavamani
- Molecular Biology Unit, Interfaculty Institute of Cell Biology, Tübingen University, Tübingen, Germany
| | - Alfred Nordheim
- Molecular Biology Unit, Interfaculty Institute of Cell Biology, Tübingen University, Tübingen, Germany
| |
Collapse
|
4
|
Frolov VA, Escalada A, Akimov SA, Shnyrova AV. Geometry of membrane fission. Chem Phys Lipids 2015; 185:129-40. [DOI: 10.1016/j.chemphyslip.2014.07.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Revised: 07/16/2014] [Accepted: 07/18/2014] [Indexed: 11/24/2022]
|