Dear colleagues, The CASP experiment is looking for prediction targets: Novel folds, membrane proteins, protein complexes and multimers, comparative modeling targets. As many of you know, the CASP community experiments have been running once every two years since 1994, collecting information on soon to be solved structures from the experimental community, and passing on sequence data to the structure modeling community so that blind predictions of structure can be collected and assessed. Over that period CASP has seen enormous progress in the quality of modeled structures, but many problems remain, and further testing of prediction methods is imperative for advancing the field. CASP organizers collect target information for a three month season every two years, and in that period we can acquire around 100 targets, sufficient to evaluate the state of the art for most types of modeling. For those of you who have not provided targets to CASP before, the procedure is simple - there is a web page for submitting targets, and a very experienced staff to deal with any queries. We don't need the structure in advance of its release by the PDB, and if we are notified early enough (a minimum of three weeks before release, more is better) there need be no delay in structure release. We need all sorts of targets and in general everything that has low coverage by the templates (<70% of the sequence length) and relatively low sequence identity to the best template (<50% ) will be appreciated. In particular, we are interested in: 1. Novel folds and membrane protein targets. Last round we observed some interesting methods developments for contact prediction and ab initio modeling, and it is important to be able to decisively evaluate their effectiveness this CASP again. 2. Protein complexes and multimers. Since the last edition of CASP, the assessment of structure prediction methods has stronger emphasis on evaluating the accuracy of quaternary structure prediction. Both oligomeric targets and complexes are of interest for the experiment. 3. A diversity of comparative modeling targets. Cases where there is fairly high sequence identity (30-50%) between the target structure and an available template are valuable for testing the degree to which model accuracy can approach that of experiment, particularly in functionally critical regions. Cases with lower sequence identity to template, right down to undetectable, are valuable for testing the ability of the methods to detect remote homologs, to overcome challenging alignment difficulties, to make use of multiple templates, and to build regions of the structure not obviously available from a template. The time table is similar to previous CASPs: The prediction season opens at the beginning of May, and will run until the end of July. We are releasing targets continuously throughout that period, as evenly spaced as possible, aiming for about 100 targets altogether. Each target will be available for prediction for a period of three weeks. For cases where longer periods are possible, these targets may be used to test refinement and data-assisted methods. It is of course important that there not be any kind of public release of the experimental structure (including things like pictures on web pages or abstracts) until after the predictions for that target are closed. As many of you know, it's fairly simple, with just two things to bear in mind. First, because of the timing framework, there needs to be at least a month between the submission date and any release of the structure. Second, we ideally need the experimental co-ordinates by the beginning of August and definitely by the end of August, so that the predictions can be assessed. At that point, they can be kept confidential if necessary, though we would like to provide them to predictors of your structure at the beginning of November at the latest, so that can see how well they have done. Participants would also usually like to be able to show slides and discuss their predictions at the meeting at the beginning of December. So, if you are currently working on an interesting protein structure suitable as prediction target for CASP , we would be most grateful if you would inform us via the target entry page: http://www.predictioncenter.org/casp12/targets_submission.cgi After CASP prediction season is over we usually publish a paper on the experimentalists' insights into the most interesting targets (see below). 2015: Some of the most interesting CASP11 targets through the eyes of their authors. Kryshtafovych A, Moult J, Baslé A, Burgin A, Craig TK, Edwards RA, Fass D, Hartmann MD, Korycinski M, Lewis RJ, Lorimer D, Lupas AN, Newman J, Peat TS, Piepenbrink KH, Prahlad J, van Raaij MJ, Rohwer F, Segall AM, Seguritan V, Sundberg EJ, Singh AK, Wilson MA, Schwede T. Proteins. 2015 Oct 16. doi: 10.1002/prot.24942. [Epub ahead of print]. PMID: 26473983. 2014: Challenging the state of the art in protein structure prediction: Highlights of experimental target structures for the 10th Critical Assessment of Techniques for Protein Structure Prediction Experiment CASP10. Kryshtafovych A, Moult J, Bales P, Bazan JF, Biasini M, Burgin A, Chen C, Cochran FV, Craig TK, Das R, Fass D, Garcia-Doval C, Herzberg O, Lorimer D, Luecke H, Ma X, Nelson DC, van Raaij MJ, Rohwer F, Segall A, Seguritan V, Zeth K, Schwede T. Proteins. 2014 Feb;82 Suppl 2:26-42. doi: 10.1002/prot.24489. Erratum in: Proteins. 2015 Jun;83(6):1198. PMID: 24318984. 2011: Target highlights in CASP9: Experimental target structures for the critical assessment of techniques for protein structure prediction. Kryshtafovych A, Moult J, Bartual SG, Bazan JF, Berman H, Casteel DE, Christodoulou E, Everett JK, Hausmann J, Heidebrecht T, Hills T, Hui R, Hunt JF, Seetharaman J, Joachimiak A, Kennedy MA, Kim C, Lingel A, Michalska K, Montelione GT, Otero JM, Perrakis A, Pizarro JC, van Raaij MJ, Ramelot TA, Rousseau F, Tong L, Wernimont AK, Young J, Schwede T. Proteins. 2011;79 Suppl 10:6-20. doi: 10.1002/prot.23196. Epub 2011 Oct 21. PMID: 22020785. Thanks, CASP organizing committee: John Moult, University of Maryland, USA Krzysztof Fidelis, University of California, Davis, USA Andriy Kryshtafovych, University of California, Davis, USA Torsten Schwede, University of Basel, Switzerland Anna Tramontano, University of Rome, Italy Get in touch: [email protected]mailto:[email protected] More information: http://www.predictioncenter.org/casp12/index.cgi Submit a target: http://www.predictioncenter.org/casp12/targets_submission.cgi