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Rai A, Shrivastava R, Vang D, Ritt M, Sadler F, Bhaban S, Salapaka M, Sivaramakrishnan S. Multimodal regulation of myosin VI ensemble transport by cargo adaptor protein GIPC. J Biol Chem 2022; 298:101688. [PMID: 35143838 PMCID: PMC8908270 DOI: 10.1016/j.jbc.2022.101688] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 01/31/2022] [Accepted: 02/02/2022] [Indexed: 11/30/2022] Open
Abstract
A range of cargo adaptor proteins are known to recruit cytoskeletal motors to distinct subcellular compartments. However, the structural impact of cargo recruitment on motor function is poorly understood. Here, we dissect the multimodal regulation of myosin VI activity through the cargo adaptor GAIP-interacting protein, C terminus (GIPC), whose overexpression with this motor in cancer enhances cell migration. Using a range of biophysical techniques, including motility assays, FRET-based conformational sensors, optical trapping, and DNA origami-based cargo scaffolds to probe the individual and ensemble properties of GIPC-myosin VI motility, we report that the GIPC myosin-interacting region (MIR) releases an autoinhibitory interaction within myosin VI. We show that the resulting conformational changes in the myosin lever arm, including the proximal tail domain, increase the flexibility of the adaptor-motor linkage, and that increased flexibility correlates with faster actomyosin association and dissociation rates. Taken together, the GIPC MIR-myosin VI interaction stimulates a twofold to threefold increase in ensemble cargo speed. Furthermore, the GIPC MIR-myosin VI ensembles yield similar cargo run lengths as forced processive myosin VI dimers. We conclude that the emergent behavior from these individual aspects of myosin regulation is the fast, processive, and smooth cargo transport on cellular actin networks. Our study delineates the multimodal regulation of myosin VI by the cargo adaptor GIPC, while highlighting linkage flexibility as a novel biophysical mechanism for modulating cellular cargo motility.
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Affiliation(s)
- Ashim Rai
- Department of Genetics, Cell Biology, and Development, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Rachit Shrivastava
- Department of Electrical and Computer Engineering, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Duha Vang
- Department of Genetics, Cell Biology, and Development, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Michael Ritt
- Department of Genetics, Cell Biology, and Development, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Fredrik Sadler
- Department of Genetics, Cell Biology, and Development, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Shreyas Bhaban
- Department of Electrical and Computer Engineering, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Murti Salapaka
- Department of Electrical and Computer Engineering, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA
| | - Sivaraj Sivaramakrishnan
- Department of Genetics, Cell Biology, and Development, University of Minnesota Twin Cities, Minneapolis, Minnesota, USA.
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Optimal Disturbance Observer Design for High Tracking Performance in Motion Control Systems. MATHEMATICS 2020. [DOI: 10.3390/math8091633] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper, a stability-driven optimal disturbance observer (DO) is proposed. The proposed method does not require any plant inverse dynamics to detect introduced disturbances or a stabilizing Q filter. It does not require additional compensators to resolve causality problems, due to the relative degree, or filters to solve instability problems of non-minimum phase plants. Using this method enables wideband and narrowband disturbances to be attenuated by simply multiplying the corresponding peak filters by the baseline weight function. Furthermore, the proposed DO guarantees the stability of closed-loop systems because the already designed outer-loop systems are considered as a target plant to be stabilized and because of the Lyapunov stability-based H∞ control. In the application example, it was confirmed that the proposed method is effective, and the position error signals were improved by 20.9% in commercial hard disk drives and 36.6% in optical image stabilization systems.
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