Subgroups

Membrane Biophysics

2010 Annual Meeting: On February 20 the Subgroup held its annual symposiumon Ion Channel Chemical Biology, which and was organized by Dan Minor of UCSF. The symposium was well-attended (standing-room only for most talks!), and provided up-to-date insights on the interface between ion channel biophysics and molecular and chemical biology. The detailed program can be found on the Subgroup’s website: http://www.biophysics.org/2010meeting/Program/Subgroups/MembraneBiophysics/tabid/796/Default.aspx.

The symposium was followed by the Cole Award dinner, where the 2010 Cole Award was presented to Ehud Isacoff of the University of California, Berkeley. Nominations for the 2011 Cole Award will be solicited next fall.

Subgroup Leadership: Dan Minor completed his term as Subgroup Chair, and the Subgroup offers its thanks for his efforts during the past year, especially with organizing the Symposium. Stephen Tucker of Oxford took over as Subgroup Chair. Paul Slesinger of the Salk Institute was elected Chair-Elect, with his term beginning at the conclusion of the 2011 Annual Meeting. Tucker is responsible for organizing the 2011 Symposium to be held at the Annual Meeting in Baltimore next year. The theme of that symposium will be Single Molecule Approaches to Ion Channels.

Subgroup E-mail list: The Subgroup has an e-mail distribution list. Members should contact Mike White (mwhite@drexelmed.edu) for information about sending out e-mails to the Subgroup membership with announcements of conferences, meetings, or other items of interest.

— Mike White, Secretary-Treasurer

Intrinsically Disordered Proteins

Annual Symposium: The annual symposium of the IDP subgroup was held in San Francisco on February 20 and focused on well-developed examples representing the diverse biological functions of IDPs.  The lecture hall was standing room only for most of the day. Co-chair Elisar Barbar introduced the first session by highlighting the IDP functions to be covered in the symposium, and included a new example from her lab, namely, formation of a polybivalent scaffold for assembly of multiprotein complexes, including dynein cargo domains. Brian Chait, the keynote speaker, discussed
his work, in collaboration with the laboratories of Michael Rout and Andrej Sali, on the structure and function of the yeast nuclear pore complex.

Co-chair Huan-Xiang Zhou’s talk focused on the principles governing the binding kinetics of ordered and disordered proteins.  Zhou proposed a new role for intrinsic disorder: it allows for the formation of protein complexes that are highly specific but short-lived. He proposed this behavior is necessary for signaling and regulation.

Andreas Matouschek discussed how the targeting signal for protein degradation consists of the proteasome binding tag, where ubiquitin is attached, and an unstructured region that serves as the proteasome initiation region. Ariele Follis, one of the recipients of the IDP Subgroup Postdoc Award, presented the next talk on NMR and ITC studies of the interaction between Bcl-xL and p53. His results suggest entropy-driven binding due to increased mobility of a large disordered loop within Bcl-xL as well as involvement of the disordered N-terminal domain of p53 in accelerating the exchange rate of complex formation. Ursula Jakob presented her work on the highly conserved bacterial heat shock protein, Hsp33. The second session opened with a talk by Joerg Gsponer who gave a proteomic view of the cellular functions of disordered proteins. Particularly intriguing is the observation that the mRNA of disordered proteins is maintained at a lower copy number than the mRNA of ordered proteins. Gsponer argues that the reduced mRNA stability for IDPs reduces the probability of unintended interactions.

Ralf Langen presented his work combining data from site-directed spin labels and molecular dynamics to build structural models for amyloid fibrils. Yaakov Levy presented coarse-grained simulations of proteins nonspecifically bound to DNA and showed that for various systems disordered tails can enhance the affinity to nonspecific DNA and facilitate the search for specific sequences.

Cheryl Arrowsmith’s talk focused on the structures of disordered histone tails.   Chung-Ke Chang the other recipient of the IDP Postdoc Award, talked about disordered regions of the SARS coronavirus capsid protein.  The session was rounded off by Gary Daughdrill’s talk on the structure and evolution of disordered proteins. Daughdrill showed recent data suggesting that single amino acid mutations can have a big effect on the equilibrium ensemble of structures for the disordered p53 transactivation domain.

The subgroup officers would like to thank all of the speakers and the co-chairs for making the 2010 IDP subgroup symposium a big success. 

—Gary W. Daughdrill, Secretary/Treasurer

Bioenergetics

Annual Symposia: The 2010 Annual Subgroup Symposia were tremendously successful. The morning symposium co-chaired by Petra Fromme, Arizona State University, and Gary Brudvig, Yale University, was entitled Photosynthesis and Solar Energy Conservation and featured speakers Dave Kramer of Washington State University, Robert  Blankenship of Washington University, John Golbeck of Pennsylvania State University, Tom Moore of Arizona State University, Stenbjorn Styring of Uppsala University, and Ann Jones of Arizona State University. The science presented was excellent and will be summarized in the next newsletter. Standing room only was available for attendees at times during the session.

Both the enthusiasm for the science and attendance were as high in the afternoon symposium, Mitochondria in Diseases co-chaired by Jan Hoeko of Thomas Jefferson University and Paolo Bernardi of University of Padova. Samir Zakhari of NIAAA/NIH gave an overview of funding opportunities at NIH for investigators in mitochondrial disease. Sarah Calvo of Broad Institute presented a talk about using integrative genomics to discover additional mitochondrial diseases.   Massimo Zeviani of Institute Neurologico Carlo Besta showed that a mutation causing multiple defects in respiratory chain proteins with accompanying decreases in cytochrome oxidase and Complex I activities in cells was in AIF (apoptosis inducing factor). The mutation truncated the protein into a completely soluble form.  Karin Nowikovsky of University of Vienna discussed how the LETM1gene product interacts strongly with the K+ channel in the mitochondrial inner membrane. In Drosophila, this interaction results in swollen mitochondrial and less mobility in flies. Mutations in the LETM1 may occur in Wolf-Hirschhorn syndrome patients. Narayan Avadhani, University of Pennsylvania, showed data supported that mitochondrial targeted cytochrome P450 has pathological consequences under conditions of high cellular cAMP. The CYP2E1 mitochondrial isoform of P450 has loosely coupled activity producing superoxide naturally which may lead to the pathology.  The last talk of the day by Daria Mochly-Rosen of Stanford University presented her work showing the up regulation of PKC protects hearts from infarctions and that ethanol can up regulate PKC.  An increase in mitochondrial aldehyde dehydrogenase activates the protection against infarcts. The diversity of talks in both sessions was simply incredible and showed bioenergetics subgroup has some outstanding science being carried out by its members.

The program of the day also included awards for our promising post docs and graduate students. The Young Bioenergeticist Award was presented to Pablo Marco Peixoto of  New York University. The Bioenergetics Student Research Achievement Award was given to Christoph Nowak from Max Planck Institute, Mainz.

At the Subgroup business meeting, it was decided that there will be an election this spring for new Council members and that the Chair of the Subgroup will continue for another year.

Lawrence Prochaska, Chair

May 2010 Table of Contents