4th ISMB Symposium 17-18 June 2010 Write-up of the event This article was written by Dr. Clare Sansom (Department of Biological Sciences, Birkbeck, University of London). The Institute of Structural and Molecular In introducing the symposium, Mary Collins, Biology holds a research symposium every two the Executive Dean of the Faculty of Life years. Its fourth such symposium was held at Sciences at University College London, one of its constituent institutions, University congratulated ISMB’s director, Gabriel College London, on June 17 and 18, 2010. As Waksman, on putting together “one of the before, the symposium brought together all highest quality structural biology meetings” researchers and postgraduate students of the that she had been to in a long time. five departments from UCL and Birkbeck Waksman, whose many honours include College making up the ISMB together for a Fellowship of the Academy of Medical two-day lecture programme. The 2010 Sciences and membership of the European symposium, attended by all researchers and Molecular Biology Organisation, is the head of postgraduate students of the five UCL and both the Department of Biological Sciences at Birkbeck departments making up the Birkbeck and the Research Department of Institute, as well as many external scientists, Structural and Molecular Biology at UCL. featured twelve excellent talks. Three each were taken from four of the Institute’s six The first programme featured structural disciplinary programmes: structural biology, biology. Its speakers may have been chosen to biophysics, chemical biology and complement each other, with one bioinformatics. Each three-lecture slot representing each of the three main structural featured one speaker from the ISMB, one from biology techniques: X-ray crystallography, the UK and another from overseas: the nuclear magnetic resonance, and electron external speakers were invariably established microscopy. The first to speak was X-ray research leaders, whereas most ISMB speakers crystallographer Laurence were promising principal investigators nearer Pearl, who moved very the beginning of their research careers. recently from London’s Institute of Cancer Research to head the School of Life Sciences at the University of Sussex, UK. Pearl has a long association with both Birkbeck and UCL as student, lecturer and professor. He described structural studies of a protein known as heat shock protein 90 (Hsp90), which is a molecular chaperone. The concept of chaperones is a very familiar one at Birkbeck, thanks to Helen Saibil’s ground-breaking work on the bacterial chaperone GroEL; they are proteins that help ISMB Symposium 2010 www.ismb.lon.ac.uk/symposium2010.html other proteins to attain and maintain their leaves the tunnel. NMR can give useful folded conformation. Hsp90, which enables information about the dynamics of these protein stability at a late stage of folding, is structures, and hence about the process of essential in eukaryotes. protein folding in vivo. Christodoulu described how “fingerprint” NMR spectra obtained at Pearl has studied the structure of this protein different points during the protein synthesis and its constituent domains since his time at process showed significant differences UCL in the 90s. The first structure of its N- between the folded and unfolded states of the terminal domain, which binds ATP, was emerging protein chain. He has used this published in 1998. Since then, he has been technique to investigate the folding of establishing the mechanism by which ATP proteins involved in diseases of protein binding drives a conformational change that aggregation, such as alpha-synuclein, which is leads to Hsp90 forming a dimer. When ATP implicated in Parkinson’s disease, and alpha-1 binds, a “lid” of protein structure folds down antitrypsin. He has obtained a high resolution over its phosphate groups, opening up a structure for the stalk protein on the intact hydrophobic surface that can be stabilised by ribosome and compared this to X-ray dimer formation. The chaperone’s substrate structures of this protein in isolation. He is proteins bind to the dimer, and ATP can be now developing cell-free methods for hydrolysed into ADP, after which the protein obtaining NMR samples of ribosomes that can relaxes back into its monomeric state. generate high-quality data faster and more Substrates that bind to Hsp90 include many cheaply than conventional methods, and is protein kinases, which are key targets for aiming to use these to probe the mechanism drugs against cancer; Pearl has published of protein folding – one of the “holy grails” of structural studies of Hsp90-kinase complexes structural biology – even more closely. in collaboration with Birkbeck electron microscopist Cara Vaughan. The last part of The name of Wolfgang Baumeister of the his talk was devoted to unpublished studies of Max-Planck Institute of Biochemistry, Hsp90 from plants in complex with co- Martinsried, Germany, is synonymous with chaperones that are necessary for its activity, technical developments in electron and he explained how these structures are microscopy and, particularly, the leading, in the light of the ATP “switch” development of electron tomography – described earlier, to new insights into the imaging in sections - as a tool for chaperone’s mechanism of action. understanding cell biology. This can The ISMB contribution to the structural produce relatively high biology programme was given by John resolution images of Christodoulou, who took up his position as a non-repetitive lecturer in the Research Department of structures the size of Structural and Molecular Biology at UCL in cells in their natural 2007. He uses NMR spectroscopy to study the environment. mechanism of protein folding on the Baumeister started his ribosome. These NMR studies of a large, talk, however, with an complex molecular machine in motion are all overview of more the more remarkable as, traditionally, NMR is recent work in his laboratory using single seen as a technique most suitable for studying particle analysis. He used as examples two relatively small molecules, and as the proteases involved in the protein degradation emerging protein chain is still rarely visible pathway, the proteasome, which chops even in X-ray structures of ribosomes. unwanted proteins into peptides about 8-12 amino acids long, and the TPII protease, Each ribosome is formed from one large and which breaks down those short peptides one small subunit, which only come together further. He can now obtain high quality to form the intact structure during protein structures of the proteasome, a cylindrical synthesis. The newly synthesised protein chain structure with a “cap” at each end, quickly emerges through a tunnel in the large subunit, and almost routinely, and is exploring its beginning to fold into its stable structure as it mechanism further with structural studies of ISMB Symposium 2010 www.ismb.lon.ac.uk/symposium2010.html the complex bound to proteins that intact, fully assembled amyloid fibrils using proteomics experiments have suggested as infra-red spectroscopy and electron interaction partners. microscopy. She discovered that structurally identical fibrils of different lengths form from Electron tomography explores the structures the assembly of globular subunits. The lengths of proteins in the context of intact cells or and physical properties of the fibrils depend organelles. Baumeister presented his studies on the environment in which they form, with of the nuclear pore complex through which slower growth producing longer fibrils. proteins are transported into and out of the Interestingly, she suggested that cell nucleus. Higher resolution structures of intermediates and short fibrils are more toxic protein components of the pore complex have to cells than the inert long fibrils; this insight been docked into a lower resolution structure may suggest new targets for intervention in of a section across the intact complex to amlyoid disease. produce a full model. He is now turning his attention to the human ribosome, which is Mark Williams, a lecturer in the Department larger than those of lower organisms and less of Biological Sciences at Birkbeck and tractable to other structural techniques. director of the ISMB Biophysics Centre, represented the “home team” in the The second programme, on biophysics, was biophysics section. His talk, intriguingly opened by Sheena Radford of the Astbury entitled “A Wet Walk in the Thicket of Centre for Structural Molecular Biology and Thermodynamics”, described some uses of Institute of Molecular and Cellular Biology, thermodynamics - the study of energy University of Leeds, UK. Radford’s research, conversion and heat changes - to aid the like Christodoulou’s, focuses understanding of protein complex formation. on protein folding, Whenever molecules interact, by either misfolding and disease, and covalent or non-covalent binding, heat is she is no stranger to the gained or lost. These gains and losses can be ISMB, having established measured and monitored over time using a productive collaborations technique known as isothermal titration with Gabriel Waksman and calorimetry (ITC). Helen Saibil. Early protein folding theories proposed a Williams illustrated the use of ITC using single mechanism for folding each sequence examples from the Hsp90 chaperone system into a single low-energy structure with a described by Pearl. The switch mechanism of single function. Folding is now known to be Hsp90 is driven by a conformational change