Skip to Content
Merck
  • Switching of myosin-V motion between the lever-arm swing and brownian search-and-catch.

Switching of myosin-V motion between the lever-arm swing and brownian search-and-catch.

Nature communications (2012-07-19)
Keisuke Fujita, Mitsuhiro Iwaki, Atsuko H Iwane, Lorenzo Marcucci, Toshio Yanagida
ABSTRACT

Motor proteins are force-generating nanomachines that are highly adaptable to their ever-changing biological environments and have a high energy conversion efficiency. Here we constructed an imaging system that uses optical tweezers and a DNA handle to visualize elementary mechanical processes of a nanomachine under load. We apply our system to myosin-V, a well-known motor protein that takes 72 nm 'hand-over-hand' steps composed of a 'lever-arm swing' and a 'brownian search-and-catch'. We find that the lever-arm swing generates a large proportion of the force at low load (<0.5 pN), resulting in 3 k(B)T of work. At high load (1.9 pN), however, the contribution of the brownian search-and-catch increases to dominate, reaching 13 k(B)T of work. We believe the ability to switch between these two force-generation modes facilitates myosin-V function at high efficiency while operating in a dynamic intracellular environment.

MATERIALS
Product Number
Brand
Product Description

Supelco
Digoxigenin, analytical standard
SKU
Pack Size
Availability
Price
Quantity
Digoxigenin, European Pharmacopoeia (EP) Reference Standard
SKU
Pack Size
Availability
Price
Quantity