English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Bidirectional cargo transport by molecular motors in cells is a complexphenomenon, in which the cargo (usually a vesicle) alternately moves inretrograde and anterograde directions. In this case, teams of oppositelypulling motors (eg., kinesin and dynein) bind to the cargo simultaneously, and`coordinate' their activity such that the motion consists of spells ofpositively and negatively directed segments, separated by pauses of varyingduration. A set of recent experiments have analyzed the bidirectional motion ofendosomes in the amoeba D. discoideum in detail. It was found that in betweendirectional switches, a team of 5-6 dyneins stall a cargo against a strongerkinesin in tug of war, which lasts for almost a second. As the mean detachmenttime of a kinesin under its stall load was also observed to be ~ 1s, we inferthat the collective detachment time of the dynein assembly must also besimilar. Here, we analyze this inference from a modeling perspective, usingexperimentally measured single-molecule parameters as inputs. We find that thecommonly assumed exponential load-dependent detachment rate is inconsistentwith observations, as it predicts that a 5-dynein assembly will detach underits combined stall load in less than a hundredth of a second. A modified modelwhere the load-dependent unbinding rate is assumed to saturate at stall-forcelevel for super-stall loads gives results which are in agreement withexperimental data. Our analysis suggests that the load-dependent detachment ofa dynein in a team is qualitatively different at sub-stall and super-stallloads, a conclusion which is likely to have implications in other situationsinvolving collective effects of many motors.

physical biology

Effectiveness of a dynein team in tug-of-war helped by reduced  load-sensitivity of detachment: evidence from study of bidirectional endosome  transport in Dictyostelium discoideum