Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP
Nucleation promoting factors (NPFs) initiate branched actin network assembly by activating Arp2/3 complex, a branched actin filament nucleator. Cellular actin networks contain multiple NPFs, but how they coordinately regulate Arp2/3 complex is unclear. Cortactin is an NPF that activates Arp2/3 compl...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
eLife Sciences Publications Ltd
2013-09-01
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| Series: | eLife |
| Subjects: | |
| Online Access: | https://elifesciences.org/articles/00884 |
| _version_ | 1828375413611560960 |
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| author | Luke A Helgeson Brad J Nolen |
| author_facet | Luke A Helgeson Brad J Nolen |
| author_sort | Luke A Helgeson |
| collection | DOAJ |
| description | Nucleation promoting factors (NPFs) initiate branched actin network assembly by activating Arp2/3 complex, a branched actin filament nucleator. Cellular actin networks contain multiple NPFs, but how they coordinately regulate Arp2/3 complex is unclear. Cortactin is an NPF that activates Arp2/3 complex weakly on its own, but with WASP/N-WASP, another class of NPFs, potently activates. We dissect the mechanism of synergy and propose a model in which cortactin displaces N-WASP from nascent branches as a prerequisite for nucleation. Single-molecule imaging revealed that unlike WASP/N-WASP, cortactin remains bound to junctions during nucleation, and specifically targets junctions with a ∼160-fold increased on rate over filament sides. N-WASP must be dimerized for potent synergy, and targeted mutations indicate release of dimeric N-WASP from nascent branches limits nucleation. Mathematical modeling shows cortactin-mediated displacement but not N-WASP recycling or filament recruitment models can explain synergy. Our results provide a molecular basis for coordinate Arp2/3 complex regulation. |
| first_indexed | 2024-04-14T07:46:17Z |
| format | Article |
| id | doaj.art-9c81eccab0a443f390780a902ae5d815 |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-14T07:46:17Z |
| publishDate | 2013-09-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-9c81eccab0a443f390780a902ae5d8152022-12-22T02:05:19ZengeLife Sciences Publications LtdeLife2050-084X2013-09-01210.7554/eLife.00884Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASPLuke A Helgeson0Brad J Nolen1Institute of Molecular Biology, University of Oregon, Eugene, United States; Department of Chemistry and Biochemistry, University of Oregon, Eugene, United StatesInstitute of Molecular Biology, University of Oregon, Eugene, United States; Department of Chemistry and Biochemistry, University of Oregon, Eugene, United StatesNucleation promoting factors (NPFs) initiate branched actin network assembly by activating Arp2/3 complex, a branched actin filament nucleator. Cellular actin networks contain multiple NPFs, but how they coordinately regulate Arp2/3 complex is unclear. Cortactin is an NPF that activates Arp2/3 complex weakly on its own, but with WASP/N-WASP, another class of NPFs, potently activates. We dissect the mechanism of synergy and propose a model in which cortactin displaces N-WASP from nascent branches as a prerequisite for nucleation. Single-molecule imaging revealed that unlike WASP/N-WASP, cortactin remains bound to junctions during nucleation, and specifically targets junctions with a ∼160-fold increased on rate over filament sides. N-WASP must be dimerized for potent synergy, and targeted mutations indicate release of dimeric N-WASP from nascent branches limits nucleation. Mathematical modeling shows cortactin-mediated displacement but not N-WASP recycling or filament recruitment models can explain synergy. Our results provide a molecular basis for coordinate Arp2/3 complex regulation.https://elifesciences.org/articles/00884Arp2/3actinWASPcortactinsingle moleculeN-WASP |
| spellingShingle | Luke A Helgeson Brad J Nolen Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP eLife Arp2/3 actin WASP cortactin single molecule N-WASP |
| title | Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP |
| title_full | Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP |
| title_fullStr | Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP |
| title_full_unstemmed | Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP |
| title_short | Mechanism of synergistic activation of Arp2/3 complex by cortactin and N-WASP |
| title_sort | mechanism of synergistic activation of arp2 3 complex by cortactin and n wasp |
| topic | Arp2/3 actin WASP cortactin single molecule N-WASP |
| url | https://elifesciences.org/articles/00884 |
| work_keys_str_mv | AT lukeahelgeson mechanismofsynergisticactivationofarp23complexbycortactinandnwasp AT bradjnolen mechanismofsynergisticactivationofarp23complexbycortactinandnwasp |