作者
Vijay S Rao, Ellisha N Marongelli, William H Guilford
发表日期
2009/1
期刊
Cell motility and the cytoskeleton
卷号
66
期号
1
页码范围
10-23
出版商
Wiley Subscription Services, Inc., A Wiley Company
简介
Tropomyosin (Tm) is one of the major phosphoproteins comprising the thin filament of muscle. However, the specific role of Tm phosphorylation in modulating the mechanics of actomyosin interaction has not been determined. Here we show that Tm phosphorylation is necessary for long‐range cooperative activation of myosin binding. We used a novel optical trapping assay to measure the isometric stall force of an ensemble of myosin molecules moving actin filaments reconstituted with either natively phosphorylated or dephosphorylated Tm. The data show that the thin filament is cooperatively activated by myosin across regulatory units when Tm is phosphorylated. When Tm is dephosphorylated, this “long‐range” cooperative activation is lost and the filament behaves identically to bare actin filaments. However, these effects are not due to dissociation of dephosphorylated Tm from the reconstituted thin filament …
学术搜索中的文章
Phosphorylation of tropomyosin extends cooperative binding of myosin beyond a single regulatory unit
VS Rao, EN Marongelli, WH Guilford - Cell motility and the cytoskeleton, 2009