Brannigan Lab

News

New book chapter on interactions of cholesterol and pentameric ligand-gated ion channels

Our new book chapter (in a great volume edited by Irena Levitan at the University of Illinois at Chicago) reviews our simulations of cholesterol and other sterols interacting with pLGICs. It also includes a brief teaser of Liam’s new coarse-grained simulations involving nAChRs in phase-separated quasi-neuronal membranes, and offers some simulation-inspired ideas for experiments with straightforward interpretations.

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PI gets tenure!

It’s official. Much appreciation to all who helped along the way –  students, postdocs, collaborators, colleagues, referees, program officers, friends, mentors, family.

Welcome to the group, Kristen!

Kristen Woods, a Masters student in Computational and Integrative Biology has joined the group! Kristen was also here at Rutgers-Camden for her undergraduate degree and decided to stay at our unique campus for graduate school. She will add to the group’s growing ‘coarse-grained’ arm, which simulates complex neuronal membranes over longer length and time scales.

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New article on interactions of general anesthetics with GABA(A) receptors in Journal of Biological Chemistry

Research on the mechanism of general anesthesia from our collaboration with Dr. Roderic Eckenhoff’s grob-a+_sideup at University of Pennsylvania, is now in press at J Biol Chem:

“A Novel Bifunctional Alkylphenol Anesthetic Allows Characterization of GABAA Receptor Subunit Binding Selectivity in Synaptosomes” by  Kellie A. Woll, Sruthi Murlidaran, Benika J. Pinch, Jérôme Hénin, Xiaoshi Wang, Reza Salari, Manuel Covarrubias, William P. Dailey, Grace Brannigan, Benjamin A. Garcia, and Roderic G. Eckenhoff.

The experimental side of this work,  carried out at Penn and Thomas Jefferson University, involved using click chemistry and photoaffinity labeling to detect differences in binding of the general anesthetic propofol* to subunits forming the GABA(A) receptor.  The experiments were done in neurons, where general anesthesia actually takes place.

On the computational side, we used a sophisticated  MD technique called Alchemical Free Energy Perturbation to calculate affinities of propofol for sites found in each interface between subunits, and we determined how small changes in the amino acids forming the sites can result in large differences in how strongly the anesthetic binds.

This was challenging because the differences are subtle, but important because GABA(A) receptors across the human central nervous system have many subtle differences with dramatic effects.

*in experiments, actually a propofol analog with modifications necessary for the experimental technique.

Welcome, Dr. Thomas Joseph!

Dr Thomas Joseph MD PhD just started a postdoc at Penn in the Anesthesiology department with our collaborators in the Eckenhoff group. Tom is a computational researcher and he’ll be a very active visitor in the Brannigan group, carrying out simulations investigating membrane protein (esp GPCR) pharmacology!

Congratulations and Good Luck, Shashank!

Shashank successfully defended his Masters thesis “Computational Study of NADH Interactions with Voltage Dependent Anion Channel” today! He’ll be moving on to the PhD Program in Biophysics at University of Rochester, in Fall 2016, continuing research on membrane proteins.

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Good Luck Reza!

Dr. Reza Salari, the group’s first postdoc, is going back into medical practice – he’ll be starting a residency in radiology at Washington University-St Louis next year, and has just left for his year-long internship at Geisinger Hospital.  The group will miss him!

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