| Autor: |
Philsang Hwang, Shih-Wei Chou, Zongwei Chen, Brian M. McDermott Jr. |
| Jazyk: |
angličtina |
| Rok vydání: |
2015 |
| Předmět: |
|
| Zdroj: |
Cell Reports, Vol 13, Iss 7, Pp 1287-1294 (2015) |
| Druh dokumentu: |
article |
| ISSN: |
2211-1247 |
| DOI: |
10.1016/j.celrep.2015.10.003 |
| Popis: |
Permanency of mechanosensory stereocilia may be the consequence of low protein turnover or rapid protein renewal. Here, we devise a system, using optical techniques in live zebrafish, to distinguish between these mechanisms. We demonstrate that the stereocilium’s abundant actin cross-linker fascin 2b exchanges, without bias or a phosphointermediate, orders of magnitude faster (t1/2 of 76.3 s) than any other known hair bundle protein. To establish the logic of fascin 2b’s exchange, we examine whether filamentous actin is dynamic and detect substantial β-actin exchange within the stereocilium’s paracrystal (t1/2 of 4.08 hr). We propose that fascin 2b’s behavior may enable cross-linking at fast timescales of stereocilia vibration while noninstructively facilitating the slower process of actin exchange. Furthermore, tip protein myosin XVa fully exchanges in hours (t1/2 of 11.6 hr), indicating that delivery of myosin-associated cargo occurs in mature stereocilia. These findings suggest that stereocilia permanency is underpinned by vibrant protein exchange. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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