News


 

Transition 2006: Seth Robia has finished his postdoc stage in Thomas Lab and moved not too far away, at Loyola University in Chicago, IL, as Assistant Professor of Physiology. Two of our Junior Scis, Kari Pedersen and Cory Paterson have been accepted into Pharma and Med Schools, so good luck to them. [July 06]

Transition 2005: Our collaborator Ed Balog moved out for a tenured position at Georgia Tech. Cheryl Miller has also left the lab, after 16 years, to prepare business models for an emerging private enterprise. [July 05]


This year Dr. Thomas was elected chair of the Gordon Muscle Conference, to be held in the summer of 2011, at Colby Sawyer College in New Hampshire. He has also been invited throughout the year to give talks at conferences and symposia such as The 11th International ATPase Conference at Woods Hole, MA in September, The Gordon Conference on Muscle Proteins, in NH in July, and invited talks at major universities in California during his semester leave of last spring. [July 05]
 

Year 2004 was very productive for Dr. Thomas and his collaborators. They published 11 articles in journals such as Proceedings of the National Academy of Sciences, Biophysical Journal, Biochemistry, Journal of Applied Physiology, and Journal of Magnetic Resonance. [January 05]

Dr. Thomas was appointed William F. Dietrich Professor in July 2004. The full name of this endowed chair is "William F. Dietrich Land Grant Chair in Fundamental Molecular/Cell Biology in the Basic Sciences."  In addition, Dr. Thomas has been elected Fellow of the Biophysical Society, the highest honor bestowed by the American Biophysical Society.  He will receive this award officially at the annual BS Meeting next February in Long Beach. [August 04]
 

Transition 2004:  During the past year, several lab members have moved on to other positions: congratulations to Josh Baker (former grad student), who has accepted a position as Assistant Professor at the University of Nevada at Reno!  Ben Mueller received his PhD and a baby at the same time, and is now completing the clinical part of his MD/PhD training. Tara Kirby moved to the NIDDK at the NIH, where she is a postdoctoral fellow doing X-ray crystallography of membrane proteins. She recently gave birth to a boy, Liam.  Wendy Nelson finished her PhD thesis and defended it, and got a postdoc position with Dr. Doris Taylor, who was recently appointed to the Medtronic-Bakken Chair in Cardiac Repair.  Former PhD student Diane Lidke and her husband Keith are both doing postdoc work in Goettingen, Germany. Jack Grinband defended his thesis and moved on to postdoctoral work in Neuroscience at Columbia. Vincent Voelz (undergrad) is in grad school at UCSF.  [November 04]

Dr. Thomas and students were featured in the Winter 2003 issue of Bio. See pages 5 (Ben Mueller receives Bloomfield Fellowship.) and 9 (Erika Helgerson and Andrew Jensen help Dr. Thomas pump iron.) BIO, Winter 2003 issue. [January 03]

Structure of Calcium Pump Regulators: We have used NMR to determine the structure of sarcolipin, a membrane protein that regulates the calcium pump in skeletal muscle. This study, a collaboration between Christine Karim in our lab and Alessandro Mascioni in Gianluigi Veglia's lab (Biochemistry, 41: 475-482), involved NMR experiments in detergent solution as well as solid-state NMR on oriented lipid bilayers.  This is the first high-resolution structure of a calcium pump regulator in its native lipid environment.  The figure at right illustrates hot spots where mutation affects function. [January 02]  More recently, we have used similar techniques to determine the structure of phospholamban, which regulates the calcium pump in cardiac muscle (Zamoon et al., Biophys J. 2004). [October 04]

 

Microwave Magic:  Yuri Nesmelov (Postdoctoral Research Associate), in collaboration with Jack Surek (grad student), has created a simple device that increases the sensitivity of EPR for small biological samples by an order of magnitude!  Yuri did some calculations on the back of an envelope (a very large one) then designed and fabricated a small hollow cylinder of potassium tantalate that focuses the microwave  magnetic field onto the sample placed inside it.  The device works for samples placed either parallel or perpendicular to the magnetic field, so it should be a big boost to Jack's thesis work on muscle fiber EPR.  Read about it in the Journal of Magnetic Resonance, 153: 7–14. 2001. [October 01]

 

 

     Actin               Myosin      

 How Muscle Works: Using EPR of spin-labeled muscle fibers, we obtained the first direct evidence that the light-chain domain rotates upon muscle activation (PNAS 95: 2944-2949; see figure). Using ATP analogs, Ingrid Brust-Mascher, Leslie Laconte, and Josh Baker showed that the orientations of the light-chain domain in the pre- and post-hydrolysis states are not significantly different from each other (Biochem 38: 12607-12613). This surprising result suggests that the ATP hydrolysis step does not induce a major structural change in myosin; rather the major stuctural change occurs upon strong actin binding and phosphate release. [98-99]







View the powerstroke movies (3.1MB) and the 3D rotation movie (1.49MB)
 

Cardiac Zipper: Minnesota Musclers Christine Karim and John Stamm and collaborators have obtained a structural model of phospholamban, a protein that helps regulate calcium pumping in the heart. The figure at left shows how leucines (red) and isoleucines (blue) form a "zipper" that holds this protein together in the membrane of a heart cell (Biochem 37: 12074-12081). Laxma Reddy, Ming Li, Bobbi Bennett, and coworkers developed a fluorescence technique for measuring oligomeric state of proteins and showed that the calcium pump binds phospholamban monomers, disrupting the zipper (Biophys J 76: 2587-2599; Biochem 38: 3954-3962). [98-99]

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Last modified on August 01, 2006