Relevance of large-scale domain motions in vivo for restraint selection

Ascertain whether large-scale domain motions that facilitate structural transitions in proteins and are captured by normal mode analysis are relevant and operative in living-cell environments, thereby validating the use of normal mode–guided restraint selection for FRET-assisted in vivo structural modeling.

Background

Normal mode analysis was used in this paper to guide restraint selection for proteins exhibiting large-scale domain motions, successfully inducing conformational changes between known in vitro states. However, whether such motions are characteristic or significant in the cellular context is not established.

Determining the relevance of these motions in vivo affects the generality and reliability of normal mode–based approaches for selecting FRET restraints when the target structures are cellular and potentially governed by different energetic landscapes than those captured by standard in vitro–calibrated force fields.