Posted in : Chemistry
NETA New York branch’s “NETA Talks Series” started with Dr. Ahmet Yildiz’s presentation on September 29, 2014 at Columbia University. He delivered a talk on his research titled “The Mechanism of Cytoplasmic Dynein Motility.” Sponsored by NETA, this talk was hosted by Dr. Ruben Gonzalez.
NETA Talks Series aims to bring together scientists in New York Metropolitan Area to provide them a platform for sharing their expertise and ideas for networking and for seeking collaboration opportunities.
Abstract: Cytoplasmic dynein is an AAA+ motor responsible for intracellular cargo transport and force generation tasks along microtubule filaments. The mechanism of dynein motility remains unclear, due to its large size (2.6 MDa) and the complexity of its structure. Using a variety of single molecule imaging and manipulation methods, we observed that dynein heads move independently along the MT, in contrast to hand over hand movement of kinesins and myosin. Dynein utilizes two distinct stepping mechanisms depending on the separation between the heads. Nucleotide-dependent release is inhibited by the tension on the linker at high separations. The two heads of a dynein dimer share the load to resist larger opposing forces. The minus-end directionality is determined by the asymmetric binding and release properties of the microtubule binding interface. Reversing the asymmetry of the microtubule binding domain resulted in plus-end directed motility. Finally, the AAA3 site is a secondary site of ATP hydrolysis that acts as a molecular switch to repurpose dynein for cargo transporting and microtubule anchor functions. On the basis of these measurements, we propose a quantitative model that describes the basis of dynein processivity, directionality and force generation.
Bio: Ahmet Yildiz received his Ph.D. in biophysics at University of Illinois Urbana-Champaign in 2004 and he became a Post-doc at the University of California San Francisco as a Jane Coffin Childs and Burroughs Wellcome Fellow. His work in single molecule fluorescence has been awarded Gregory Weber International Prize in Biological Fluorescence in 2005 and the Young Scientist Award by Science Magazine in 2006. In August 2008, he joined the physics department at UC Berkeley.
More info about Dr. Ahmet Yildiz and his lab: http://research.physics.berkeley.edu/yildiz/
Theme: The Mechanism of Cytoplasmic Dynein Motility
Date: September 29, 2014 from 4:30 pm to 5:30 pm EDT
Location: Morningside Campus Room 209 Havemeyer
3000 Broadway New York, NY 10027
Keywords: Cytoplasmic Dynein Motility