Direct measurement of Vorticella contraction force by micropipette deflection
Abstract
The ciliated protozoan Vorticella convallaria is noted for its exceptionally fast adenosine triphosphate‐independent cellular contraction, but direct measurements of contractile force have proven difficult given the length scale, speed, and forces involved. We used high‐speed video microscopy to image live Vorticella stalled in midcontraction by deflection of an attached micropipette. Stall forces correlate with both distance contracted and the resting stalk length. Estimated isometric forces range from 95 to 177 nanonewtons (nN), or 1.12 nN·μm−1 of the stalk. Maximum velocity and work are also proportional to distance contracted. These parameters constrain proposed biochemical/physical models of the contractile mechanism.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 01, 2017
- Source ID
- 10.1002/1873-3468.12577
Entities
People
- Danielle France
- Jonathan Tejada
- Paul Matsudaira
Organizations
- Massachusetts Institute of Technology
- The Institute for Collaborative Biotechnologies