PURIFICATION OF INITIATOR C FROM ESCHERICHIA COLI - A PROTEIN WHICH BINDS MESSENGER RNA AND INITIATOR TRNA TO 30 S RIBOSOME

Attachment of 30 s ribosomes to nascent messenger RNA, which can be studied by electron microscopic quantitation of the number of ribosomes bound to bacteriophage T4 DNA transcribed with RNA polymerase, requires the presence of initiator protein C(F2). On the other hand, C also promotes the binding of N-formylmethionyl-tRNA to the 30 s ribosome. Evidence is presented that both mRNA and initiator tRNA binding activities are due to the same protein. © 1969.