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Jianjun  Pan

Jianjun Pan

Jianjun Pan
Associate Professor


Office: ISA 4206
Phone: 813/974-2943
Lab: ISA 4045, 4049
Email: panj AT



Ph.D. Physics, 2009, Carnegie Mellon University


Our primary research interests are centered on unveiling fundamental mechanisms dictating important membrane-associated biological processes. We use a multitude of approaches to achieve our goal.  Experimentally, we use high-resolution atomic force microscopy to interrogate structural and dynamical properties of biological composites. Theoretically, we collaborate closely with molecular dynamic simulators to decipher short time scale events that are responsible for meso- and macro-scale properties discerned from experimental measurements. 

Research Highlights:
1. Characterization of membrane structural and mechanical properties is important for elucidating molecular mechanisms of many membrane active antimicrobial peptides (AMPs). We use solution atomic force microscopy, force spectroscopy, micropipette aspiration, and vesicle leakage to study perturbations of model lipid membranes exerted by natural and synthetic AMPs.

2. Lipid membranes are suggested as potential targets by toxic protein aggregates. Using solution atomic force microscopy and several complementary techniques, we have studied aggregates (i.e. oligomers and fibrils) formed by a synthetic polyglutamine peptide. We also determined their disruptive effect on model lipid membrane's physical properties.

3. The M2 protein of influenza A virus was proposed to play a major role in virus packaging, assembly, and budding. Using solution atomic force microscopy and fluorescence microscopy, we studied the transmembrane domain of the M2 protein (M2TM) interacting with planar lipid bilayers and free-standing giant unilamellar vesicles (GUVs). We found that M2TM preferentially partitioned into the liquid-disordered phase, M2TM increased the miscibility transition temperature of phase coexisting GUVs, and M2TM can elicit an array of vesicle shapes mimicking virus budding.

4. Lipid rafts were proposed to play an important role in a plethora of membrane-associated events (e.g. protein signaling and trafficking). Much of lipid raft properties can be inferred from the phase behavior of multi-component model lipid membranes. Using solution atomic force microscopy and fluorescence microscopy, we have obtained micron- and nanometer-sized phase separation in ternary and quaternary lipid bilayers.