Fig. 7: Locating the structure alteration of CRABPⅡ between AC and HC induced by ligand binding.

a the PLOT^VSS generated by MELO for locating the variations in secondary structure. Three regions of obvious alterations were highlighted, which included the second helix (purple box), βD loop (brown box), and βJ loop (umber box). T: β-turn; E: β-strand; B: β-bridge; H: α-helix; I: Π-helix; G: 310-helix; P: κ-helix. b the PLOT^SPS generated by MELO for locating the shifts among protein segments with darker color showing regions of significant displacements. The second helix (purple box) and the βE-βF loop (umber box) were captured by MELO as key regions of segmental shifts. c structural superimpositions of apo-CRABPII (AC, PDB:1BLR) and holo-CRABPⅡ (HC, PDB:6HKR), providing main variations in secondary structures (such as the second helix (purple box), the βD loop (brown box) & the βJ loop (umber box). d shift was discovered for the second helix. e shift was identified for the βE-βF. All in all, the MELO was found capable of identifying not only the variation in secondary structure but also the shift among protein segments in the studied protein of cellular retinoic acid-binding protein 2.