Cardiac V 1 And V 3 Myosins Differ in Their Hydrolytic and Mechanical Activities In Vitro

Author:

VanBuren Peter1,Harris David E.1,Alpert Norman R.1,Warshaw David M.1

Affiliation:

1. From the Departments of Molecular Physiology and Biophysics (D.E.H., N.R.A., D.M.W.) and Cardiology (P.V.B.), University of Vermont, Burlington.

Abstract

Abstract The two mammalian cardiac myosin heavy chain isoforms, α and β, have 93% amino acid homology, but hearts expressing these myosins exhibit marked differences in their mechanical activities. To further understand the function of these cardiac myosins as molecular motors, we compared the ability of these myosins to hydrolyze ATP and to both translocate actin filaments and generate force in an in vitro motility assay. V 1 myosin has twice the actin-activated ATPase activity and three times the actin filament sliding velocity when compared with V 3 myosin. In contrast, the force-generating ability of these myosins is quite different when the total force produced by a small population of myosin molecules (>50) is examined. V 1 myosin produces only one half the average cross-bridge force of V 3 myosin. With discrete areas of primary structural heterogeneity known to exist between α and β heavy chains, the differences we report in the hydrolytic and mechanical activities of the motors are explored in the context of potential structural and kinetic differences between the V 1 and V 3 myosins.

Publisher

Ovid Technologies (Wolters Kluwer Health)

Subject

Cardiology and Cardiovascular Medicine,Physiology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3