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Engineering Approaches to Biomolecular Motors: From in vitro to in vivo Poster Abstracts
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24-POS
Board 24
Nonprocessive Motor Ensemble for Large Vesicle Trafficking
Takeshi Sakamoto
1,2
, Justin Raupp
1
, Yuwen Mei
1
, Xuequn Chen
2
.
2
Wayne State University, Detorit, MI, USA.
1
Wayne State Universitry, Detorit, MI, USA,
Molecular motors are protein machines that perform numerous cellular functions including cell
motility, contraction, organelle transport, and cell division. Cargo transport is an essential
cellular process indispensible for life across phylogeny. Class V myosin (MyoV) is the actin-
based molecular motors implicated in organelle and vesicle transport and has been found in
many species ranging from yeast to mammals. In vertebrates, there are three class V myosin
genes encoding, named MyoVa, MyoVb, and MyoVc. MyoVc is kinetically weak affinity for
actin filament, called non-processive, than MyoVa / Vb, though MyoVc binds on vesicles and
believed involving vesicle trafficking.
MyoVc is a low duty ratio, non-processive motor unable to move continuously along actin
filaments though it is believed to participate in secretory vesicle trafficking in vertebrate cells.
Previously two dimers of Myo5c molecules on a DNA scaffold increased the probability of
rebinding to F-actin and enabled processive steps along actin filaments, which could be used for
collective cargo transport in cells. We measured the processivity and velocity (100 nm/s) of
purified Zymogen granules in vitro. Mass spectrometry analysis showed a few myosins (MyoVc
and MyoI) binds on ZGs. Kinesin and/or Dynine may bind the surface of ZGs. To understand the
ZG’s vesicle transportation and the function of molecular motors in cells, we observed the ZGs
movement in acinar cells.