Feng Ye

Feng Ye Department of Medicine, UCSD Leichtag Building Room 149-M 9500 Gilman Drive, Mail Code 0726 La Jolla, CA 92093-0726 phone: 858-822-6496 feye@ucsd.edu

Structure of Integrins in the Membrane

I was a Ph.D. student in Prof. Taylor's laboratory from 2002-2005. My project was to obtain a 3-D image of an integrin in both the active and inactive states while the protein was embedded in a lipid bilayer, its normal state in the cell. I isolated and purified the α-IIbΒ3 integrin in a triton solubilized form from platelets, removed any active integrins by chromatography, and reincorporated the inactive integrins into small unilamellar vesicles. I collected tilt series of these integrins-vesicles in both the inactive state as isolated from the cells and also in an activated state using Mn⁺⁺ and obtained 3-D images using electron tomography. These specimens were preserved in the frozen hydrated state. Subvolumes of individual integrins were extracted, aligned and classified to produce 3-D images with improved signal-to-noise ratio so that the molecular conformation could be elucidated. Publication of this work is currently in progress.

PUBLICATIONS

• Fung Ye, Jun Liu & Kenneth A. Taylor. alphaIIb beta 3 integrin activation visualized in a membrane environment by cryoelectron tomography (in revision)
• Feng Ye, Jun Liu, Hanspeter Winkler and Kenneth A. Taylor. Integrin α IIbΒ3 in a membrane environment remains the same height after Mn⁺⁺ activation when observed by cryo-electron tomography. J. Mol. Biol., (in press, 2008).