As architects, they start by looking for structural motifs and ways in which the forms naturally grow. (mercercontemporary.com)
For the past decade or so, they have been exposing a nested hierarchy of structural motifs in genomes that are every bit as elemental to the identity and activity of each cell as the double helix. (scientificamerican.com)
Hence AMPA and NMDA receptor channels contain common structural motifs in their TM2 segments that are responsible for some of their ion selectivity and conductance properties. (science.sciencemag.org)