Figure 7. Intersubunit Bridges in the Canine Ribosome
(A) Known rotations of the body and head of the small subunit
are indicated by arrows on the canine ribosome. Positions of the
bridges specific to eukaryotic ribosomes and bridge 2e are
(B) A reverse view of the ribosome shows that
the ebs form a contiguous line along the lateral edge of the
small subunit and are also present beneath the subunits (eb11).
(C) An unmodeled C-terminal extension of L37ae contacts h22
in bridge 2e.
(D) An α helix originates from S-IV and
extends across the subunit interface to form eb8. Additional
density from L7ae and ES31 helps to form this bridge near the L1
stalk helix (H76).
(E) Bridge 9 (eb9) involves extensive
interactions between L30e and S13e. The N-terminal helix of S13e
is flipped out to interact with protein S-IX.
S-VII forms a bridge between ES3^S and ES41. An icon view in the
lower left shows the proximity of eb11 and eb12.
C-terminal extension of L19e forms a long helix that crosses the
intersubunit gap to interact with one branch of ES6^S.
The above figure is reprinted
from an Open Access publication published by Cell Press: