期刊
ANNUAL REVIEW OF PHYSIOLOGY, VOL 80
卷 80, 期 -, 页码 327-351出版社
ANNUAL REVIEWS
DOI: 10.1146/annurev-physiol-021317-121254
关键词
muscle contraction; titin; protein folding; polymer physics; single molecule; force spectroscopy
类别
资金
- US National Institutes of Health (NIH) [GM116122, HL061228]
- National Science Foundation [DBI-1252857]
- NIH [5F30HL129662]
- Fundacion Ramon Areces
Single-molecule atomic force microscopy and magnetic tweezers experiments have demonstrated that titin immunoglobulin (Ig) domains are capable of folding against a pulling force, generating mechanical work that exceeds that produced by a myosin motor. We hypothesize that upon muscle activation, formation of actomyosin cross bridges reduces the force on titin, causing entropic recoil of the titin polymer and triggering the folding of the titin Ig domains. In the physiological force range of 4-15 pN under which titin operates in muscle, the folding contraction of a single Ig domain can generate 200% of the work of entropic recoil and occurs at forces that exceed the maximum stalling force of single myosin motors. Thus, titin operates like a mechanical battery, storing elastic energy efficiently by unfolding Ig domains and delivering the charge back by folding when the motors are activated during a contraction. We advance the hypothesis that titin folding and myosin activation act as inextricable partners during muscle contraction.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据