Dear ChimeraX team, Two selection-related questions: 1. I'm looking for a way to combine multiple sequence based selections into one selection but I wasn't able to find a way to do this. The use case is, I have a lot of models that have these two proteins and I would like to use them together for superposition (via align command against Calphas). I would normally refer to them by chain ID, but here these are not consistently assigned so I need to use the sequence for selection. 1. Is it possible to have a named, sequence-based selection that, when called, would perform the selection? This would save a lot of pain when writing scripts for sequence based selections. Cheers, EP -- Esa-Pekka Kumpula, PhD Senior Postdoctoral Researcher Laboratory of Structural Biology Institute of Biotechnology Helsinki Institute of Life Science HiLIFE University of Helsinki www.helsinki.fi/lsb<http://www.helsinki.fi/lsb>