microtubules are hollow cylinders consisting of tubulin, a heterodimer of α- and β-tubulin. In vivo microtubules are composed of 13 tubulin protofilaments, strings of consecutive αβ–αβ tubulin ...

During the elongation cycle of protein biosynthesis on the ribosome, elongation factor G (EF-G), a GTPase, facilitates the translocation of the A- and P-site tRNAs to the P and E sites, respectively, ...