Alpbach special issue.
http://dx.doi.org/10.1016/j.jsb.2014.05.004 1047-8477/ 2014 Published by Elsevier Inc. The 6th Workshop on Coiled-Coils, Collagen and Fibrous Proteins was held at Alpbach, Austria in September 2013. As usual, it attracted delegates with structural interests in those protein systems where the coiled-coil motif plays an important role. These days, of course, this is not confined to the world of fibrous proteins but is found equally commonly in the globular ones too. Developments in both biophysical and biochemical aspects of the field proved a fertile ground for discussion, as did the interactions between those scientists whose interests lay primarily either in the extracellular proteins or the intracellular proteins (but, prior to Alpbach, rarely in both). The Special Issue presented here reveals a selection of the contributions made at the Workshop, and thereby provides a snapshot of where the field is now and where it is going over the next few years. Increasing numbers of crystal structures of the coiled-coil conformations observed in globular and fibrous proteins have revealed many more details of the relationship between amino acid sequence and the conformation observed. There is, of course, much more to the coiled coil than its structure alone, and the role of specific sequences that bestow a distinct function on these motifs has become more evident. Another point of considerable interest to emerge was that the conformations of the short regions between stretches of continuous heptad substructure are now describable at the atomic level. This refers not only to the wellestablished stutters, stammers and skips (deletions of three, four and six residues, respectively) where previous crystal data and modeling studies have been presented, but also now to the three other less common possibilities (deletions of one, two and five residues). An analogous study of breaks in the triplet phasing in collagen sequences was also presented. It has also became clear that the silk structures, and not those with the short sequence repeats that dominated the field in its early years, are increasingly being studied in detail, and these too are proving extremely informative. Some aspects of the 6th Workshop were different from those that preceded it. Importantly, Andrei Lupas and Dek Woolfson have taken over from John Squire and me as the new organizers. In so doing they have highlighted a variety of globular coiled-coil protein systems as well as biomaterials and silks. Core areas of research in the collagens and other a-fibrous proteins have been retained, of course, as has the compilation of a Special Issue of the Journal of Structural Biology. Our thanks go to the Editor, Dr. Alasdair Steven, for his support and encouragement in this particular venture. His support of the specialized field of coiled coils and fibrous proteins remains of great importance to us. In summary, protein researchers of all types will find much of interest in this Special Issue and the reader is strongly encouraged to investigate some of the treasures included.