On the role of protein S4 N-terminal residues I through 30 in 30S ribosome function

L. M. Changchien, J. Schwarzbauer, M. Cantrell, G. R. Craven

Research output: Contribution to journalArticlepeer-review

10 Scopus citations


30S ribosomal protein S4 contains a single cysteine residue at position 31. We have selectively cleaved the peptide bond adjacent to this residue using the reagent 2-nitro-5-thiocyano-benzoic acid. The two resultant fragments were purified. The smaller S4-fragment (1-30) was found to be incapable of interacting with 16S RNA directly. This fragment also is not incorporated into a particle reconstituted from 16S RNA and 20 purified proteins with S4 missing. In contrast, the large S4- fragment (31-203) appears to be fully functional in ribosome assembly. Replacement of S4 with this fragment in the reconstitution reaction leads to a complete 30S ribosome containing all 30S proteins. This particle has a full capacity to bind poly U but has lost all activity for poiy U directed phe-tRNA binding. We therefore propose that the N-terminus of protein S4 is not critical for ribosome assembly but is essential for tRNA binding.

Original languageEnglish (US)
Pages (from-to)2789-2800
Number of pages12
JournalNucleic acids research
Issue number8
StatePublished - Aug 1978
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Genetics


Dive into the research topics of 'On the role of protein S4 N-terminal residues I through 30 in 30S ribosome function'. Together they form a unique fingerprint.

Cite this