Figure 2

A comparison of the PRC-barrel with the analogous β-barrels, namely the SH3-like barrel and the OB fold. (a) The representative of the SH3-like barrel is the dihydrofolate reductase subunit (PDB 1vie) and (b) the representative of the OB fold is the cold-shock protein S1-like RNA-binding domain (PDB 1mjc). Note the difference in packing of the last strand of the OB fold with respect to the first strand in the SH3-like barrel and (c) the PRC-barrel. In the case of the OB fold, note the difference in orientation of the second strand with respect to the first as compared to the other two β-barrels.