Reconstitution of Qβ Replicase Lacking Subunit α with Protein-Synthesis-Interference Factor i.

We have isolated a form of Qβ replicase lacking subunit α and shown that it is deficient in the utilization of Qβ-plus strand RNA as template but competent to utilize Qβ-minus strands, poly(C) and "6-S" RNA. The functional identity of subunit α and protein-synthesis-inhibition factor i was proven by their equivalent capacity to restore full Qβ RNA-directed activity of α-less replicase. [ABSTRACT FROM AUTHOR]