Molecular Motors
Molecular motors are proteins which convert chemical energy to mechanical energy within living cells. My work has specifically focused on processive linear molecular motors which carry cargos along microtubules, especially kinesin. Since these motors are at the nanoscale and their progression requires chemical reactions, the models to describe their motion are typically stochastic.
My research has focused on creating more biologically relevant models which incorporate the interaction between chemical events and physical diffusion of the individual heads of kinesin. I have worked with William Hancock of the Bioengineering Department at Penn State and members of his lab to build these models and to link them with biological experiments. Through these efforts to connect models to experiments, we have also created statistical methods for the images that result from fluorescence microscopy experiments. This work was supported by the NSF/NIH joint initiative in mathematical biology DMS 0714939.
More recently, I have been working with an inter-university team ( William Hancock, Peter Kramer, and Scott McKinley ) to study groups of molecular motors, both kinsein and dynein, pulling a single cargo. Kinesin moves toward the plus end of a microtubule, while dynein moves towards the negative end. Knocking down one should cause increase movement in the opposite direction; however, this does not seem to happen within a cellular environment. We are focused on understanding these surprising contradictions with the hope of better understanding the regulation of motor-cargo complexes in intracellular transport. This team is currently being supported by the NIH.
- Penalized KS method to fit data sets with power law distribution over a bounded subinterval
w F Olmez, PR Kramer, DR Schmidt, J Best
- A kinetic dissection of the fast and superprocessive kinesin-3 KIF1A reveals a predominant one-head-bound state during its chemomechanical cycle
w TM Zaniewski, AM Gicking, WO Hancock
- Effective behavior of cooperative and nonidentical molecular motors
w JJ Klobusicky, J Fricks, Peter R Kramer
- Renewal reward perspective on linear switching diffusion systems in models of intracellular transport
w Maria-Veronica Ciocanel, Peter R Kramer, Scott A McKinley
- Insights into kinesin-1 stepping from simulations and tracking of gold nanoparticle-labeled motors
w Keith J Mickolajczyk, Annan SI Cook, Janak P Jevtha, William O Hancock
- Load‐dependent detachment kinetics plays a key role in bidirectional cargo transport by kinesin and dynein.
w KG Ohashi, L Han, B Mentley, J Wang, WO Hancock
- Analysis of single particle diffusion with transient binding using particle filtering.
w Jason Bernstein
- Estimating Velocity for Processive Motor Proteins with Random Detachment.
w John Hughes, Shankar Shastry, and William Hancock
- Asymptotic Analysis of Microtubule-Based Transport by Multiple Identical Molecular Motors
w Scott McKinley, Avanti Athreya, and Peter Kramer
- Kinesins with Extended Neck Linkers: A Chemomechanical Model for Variable-Length Stepping
w John Hughes and William Hancock
- A Matrix Computational Approach to Kinesin Neck Linker Extension
with John Hughes and William Hancock
- Monte Carlo Analysis of Neck Linker Extension in Kinesin Molecular Motors
w Matthew Kutys and William Hancock
- A Mixture Model for Quantum Dot Images of Kinesin Motor Assays
w John Hughes
- Likelihood Inference For Particle Location In Fluorescence Microscopy
w John Hughes and William Hancock
- Molecular Motors, Brownian Ratchets, and Reflected Diffusions
w Amarjit Budhiraja
- A numerical algorithm for investigating the role of the motor-cargo linkage in molecular motor driven transport
w Timothy Elston and Hongyun Wang
Matlab code for the Fricks, Wang, and Elston paper.
- Biomolecular Motors and Diffusion Ratchets (PhD thesis)