Quantification analysis of translation initiation signal sequences in vertebrate mRNAs.

The signal for directing the position of translation initiation in vertebrate mRNAs requires not only ATG initiation codon but also sequences flanking the initiation codon. A consensus sequence, (GCC) GCC (A or G) CCATGG has been proposed for the signal, but actual initiation sequences differ from it in a greater or lesser degree. In the present report, the translation initiation signal sequences of rat preproinsulin mRNA and its mutant mRNAs were analyzed using a quantification method, which demonstrates that strength of the signal plays important role in determining efficiency of initiation reaction.