It is well established that the ability of CrPV IRES and HCV IRES to directly bind to small ribosomal subunit is due to their inherent nature to fold into a compact three-dimensional structure containing specific ribosome binding domains [16], [18], [65], [66].
In the body, collections of these subunits fit together like Legos to form proteins that bind to small molecules and other proteins – exactly what any drug must do.
When this finding is combined with the results already discussed, the picture that emerges is that within the PII trimer, the subunit binding the receptor must be bound by the small molecule effectors, and the other subunits of the trimer can influence its activity by intersubunit signaling when they bind to small molecule effectors.
Several proteins referred to as initiation factors can bind to the small subunit of the ribosome, which itself is composed of an RNA molecule and numerous proteins, and form a pre-initiation complex (or PIC for short).
MRNA is then bound to the small subunit, aligning the start codon to the peptidyl site of the mitoribosome.
In contrast, more than 50% of the labeled CrPV IRES RNA was bound to the small subunit (Fig. 6A).
We found a transition mutation causing a valine-to-methionine substitution at a highly conserved residue within the domain that is predicted to bind the small subunit (RnrS ).
Further analysis indicated that GLV IRES may not require a pre-initiation complex for initiating translation both in Giardia and in RRL, nor does it bind to Giardia small ribosomal subunit in vitro.
Elg1 binds the small subunits of the RFC complex [4] and, similarly to the RFC complex, is assumed to act during replication to load or unload the processivity clamp PCNA.
In this process, the initiation factor complexes eIF2, eIF3, and the cap-binding protein complex (eIF4f) associate to bind the ribosomal small subunit complex (40S) (reviewed in [ 3]).
