PUBLICATION
The Stereociliary Paracrystal Is a Dynamic Cytoskeletal Scaffold In Vivo
- Authors
- Hwang, P., Chou, S.W., Chen, Z., McDermott, B.M.
- ID
- ZDB-PUB-151110-7
- Date
- 2015
- Source
- Cell Reports 13(7): 1287-94 (Journal)
- Registered Authors
- Chou, Shih-wei, Hwang, Philsang, McDermott Jr., Brian M.
- Keywords
- none
- MeSH Terms
-
- Animals
- Cytoskeleton/metabolism*
- Cytoskeleton/ultrastructure
- Eye Proteins/metabolism
- Hair Cells, Auditory/metabolism
- Hair Cells, Auditory/ultrastructure
- Microfilament Proteins/metabolism
- Myosins/metabolism
- Protein Transport
- Stereocilia/metabolism*
- Stereocilia/ultrastructure
- Zebrafish
- Zebrafish Proteins/metabolism
- PubMed
- 26549442 Full text @ Cell Rep.
Citation
Hwang, P., Chou, S.W., Chen, Z., McDermott, B.M. (2015) The Stereociliary Paracrystal Is a Dynamic Cytoskeletal Scaffold In Vivo. Cell Reports. 13(7):1287-94.
Abstract
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.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping