RRC ID |
20965
|
著者 |
Uyeda TQ, Iwadate Y, Umeki N, Nagasaki A, Yumura S.
|
タイトル |
Stretching actin filaments within cells enhances their affinity for the myosin II motor domain.
|
ジャーナル |
PLoS One
|
Abstract |
To test the hypothesis that the myosin II motor domain (S1) preferentially binds to specific subsets of actin filaments in vivo, we expressed GFP-fused S1 with mutations that enhanced its affinity for actin in Dictyostelium cells. Consistent with the hypothesis, the GFP-S1 mutants were localized along specific portions of the cell cortex. Comparison with rhodamine-phalloidin staining in fixed cells demonstrated that the GFP-S1 probes preferentially bound to actin filaments in the rear cortex and cleavage furrows, where actin filaments are stretched by interaction with endogenous myosin II filaments. The GFP-S1 probes were similarly enriched in the cortex stretched passively by traction forces in the absence of myosin II or by external forces using a microcapillary. The preferential binding of GFP-S1 mutants to stretched actin filaments did not depend on cortexillin I or PTEN, two proteins previously implicated in the recruitment of myosin II filaments to stretched cortex. These results suggested that it is the stretching of the actin filaments itself that increases their affinity for the myosin II motor domain. In contrast, the GFP-fused myosin I motor domain did not localize to stretched actin filaments, which suggests different preferences of the motor domains for different structures of actin filaments play a role in distinct intracellular localizations of myosin I and II. We propose a scheme in which the stretching of actin filaments, the preferential binding of myosin II filaments to stretched actin filaments, and myosin II-dependent contraction form a positive feedback loop that contributes to the stabilization of cell polarity and to the responsiveness of the cells to external mechanical stimuli.
|
巻・号 |
6(10)
|
ページ |
e26200
|
公開日 |
2011-1-1
|
DOI |
10.1371/journal.pone.0026200
|
PII |
PONE-D-11-12001
|
PMID |
22022566
|
PMC |
PMC3192770
|
MeSH |
Actin Cytoskeleton / metabolism*
Dictyostelium / cytology*
Dictyostelium / metabolism*
Gene Knockout Techniques
Green Fluorescent Proteins / metabolism
Models, Biological
Molecular Probes / metabolism
Mutant Proteins / chemistry
Mutant Proteins / metabolism
Myosin Type II / chemistry*
Myosin Type II / metabolism*
Phalloidine / analogs & derivatives
Phalloidine / metabolism
Protein Structure, Tertiary
Protein Transport
Rhodamines / metabolism
|
IF |
2.74
|
引用数 |
94
|
WOS 分野
|
CELL BIOLOGY
|
リソース情報 |
細胞性粘菌 |
S00100
S00005
S00464
S00465
S00468
G90088
G90089
G90090
G90091
G90092
G90093
G90094
G90098
G90096 |