Physical and Functional Homology between Ribosomal Protein S1 and Interference Factor i

Hiroshi Inouye, Yaakov Pollack, Jean Petre

Research output: Contribution to journalArticlepeer-review

52 Scopus citations


The homology between the 30‐S ribosomal protein S1 and interference factor i has been investigated. The two proteins are indistinguishable by gel electrophoresis under various conditions. Similar peptides are obtained by cleavage with cyanogen bromide. After labelling with N‐ethylmaleimide, enzymatic digestion yields homologous labelled peptides. This homology is confirmed by immunological data. Characteristic activities of the two proteins have been compared. Both bind polyuridylic acid and stimulate polypeptide synthesis on this template by S1‐depleted ribosomes. Furthermore, S1 inhibits the translation of the coat protein cistron on MS2 RNA, while it has little effect on the overall translation of T4 mRNA, two characteristic properties of interference factor i. S1 and factor i are thus physically and functionally indistinguishable, which suggests that they have identical polypeptide chains. Implications are discussed in terms of function.

Original languageEnglish
Pages (from-to)109-117
Number of pages9
JournalEuropean Journal of Biochemistry
Issue number1
StatePublished - 1 Jan 1974
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry


Dive into the research topics of 'Physical and Functional Homology between Ribosomal Protein S1 and Interference Factor i'. Together they form a unique fingerprint.

Cite this