Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 7 (1), 245-51

Ribosomal Initiation From an ACG Codon in the Sendai Virus P/C mRNA


Ribosomal Initiation From an ACG Codon in the Sendai Virus P/C mRNA

J Curran et al. EMBO J.


The Sendai virus P/C mRNA expresses the P and C proteins from alternate reading frames. The C reading frame of this mRNA, however, is responsible for three proteins, C', C and Y, none of which appear to be precursors to each other in vivo. Using site-directed and deletion mutagenesis of the P/C gene cloned in SP6 and in vitro translation of the mRNAs, we show that the 5' most proximal initiation codon of the mRNA is an ACG at position 81, responsible for C' synthesis. The succeeding initiation codons, all ATGs, are responsible for the P protein (position 104), the C protein (position 114) and the Y protein(s) (either positions 183 or 201). Examination of the relative molar amounts of the C', P and C proteins found in vivo suggests that an ACG in an otherwise favorable context is almost as efficient for ribosome initiation as an ATG in a less favored context, but only 10-20% as efficient as an ATG in a more favored context. The judicious choice of increasingly more favorable initiation codons in the P/C gene allows multiple proteins to be made from a single mRNA.

Similar articles

See all similar articles

Cited by 76 PubMed Central articles

See all "Cited by" articles


    1. J Virol. 1974 Feb;13(2):261-8 - PubMed
    1. J Gen Virol. 1987 Sep;68 ( Pt 9):2515-9 - PubMed
    1. Proc Natl Acad Sci U S A. 1975 Oct;72(10):3961-5 - PubMed
    1. Virology. 1976 Jan;69(1):116-31 - PubMed
    1. Virology. 1978 Feb;84(2):469-78 - PubMed

Publication types

LinkOut - more resources