Changes around the five-fold channels.

<p>Lateral view of the five-fold axis in the 80S particle (A) and the native capsid (B) of HRV2. VP1 protein is shown in blue, VP3 in red and VP4 in yellow. For clarity, only two subunits of VP1 are displayed. In the native structure, the pocket factor is displayed as orange sticks and the N-terminal α-helix (residues 1001 to 1013, not present in the crystal structure of HRV2) has been modeled according to its position in the structure of HRV16 and is shown in grey. The close-ups at the right show a top view of the five-fold axes, with residues His1138 and His1173 from the five symmetry related VP1 subunits displayed as yellow sticks. (C) Close-up of the N-terminal region of VP1 from the HRV2 native structure, seen from the inside of the virion. VP1 is shown in blue, VP2 in green and VP3 in red; the first residue seen in the 80S density map (Arg1062) is indicated with an asterisk and from then on VP1 is colored in cyan. The side chains of the residues involved in acid-labile interactions stabilizing the conformation of the VP1 N-terminus are shown as sticks and explicitly labeled.