Cytoplasmic dynein is the main minus-end directed motor protein to walk along microtubules inside cells, but the complex structure has made dynein difficult to purify and study in vitro. This study aims to purify dynein and label the motors with fluorophores or beads to probe their stalling force, step size, and processivity. Dynein coated beads will be grabbed by optical tweezers to detect steps and forces. Single fluorescent dyneins can be accurately located as they walk along microtubules using total internal reflection fluorescence microscopy and fluorescence imaging with one nanometer accuracy to determine the step size and processivity. This work will not only reveal the inner workings of the dynein motor protein, but will also further inform us of dynein malfunction related to motor neuron diseases.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
1F32GM075754-01
Application #
6994090
Study Section
Special Emphasis Panel (ZRG1-F04B (20))
Program Officer
Basavappa, Ravi
Project Start
2005-09-01
Project End
2008-08-31
Budget Start
2005-09-01
Budget End
2006-08-31
Support Year
1
Fiscal Year
2005
Total Cost
$43,976
Indirect Cost
Name
University of Pennsylvania
Department
Physiology
Type
Schools of Medicine
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Hendricks, Adam G; Perlson, Eran; Ross, Jennifer L et al. (2010) Motor coordination via a tug-of-war mechanism drives bidirectional vesicle transport. Curr Biol 20:697-702
Ross, Jennifer L; Shuman, Henry; Holzbaur, Erika L F et al. (2008) Kinesin and dynein-dynactin at intersecting microtubules: motor density affects dynein function. Biophys J 94:3115-25
Ross, Jennifer L; Wallace, Karen; Shuman, Henry et al. (2006) Processive bidirectional motion of dynein-dynactin complexes in vitro. Nat Cell Biol 8:562-70