Identification of the RNA binding regions of SRP68/72 and SRP72 by systematic mutagenesis of human SRP RNA

Jiaming Yin, Elena Iakhiaeva, Elena Menichelli, Christian Zwieb

Research output: Contribution to journalArticle

8 Scopus citations

Abstract

Within the large domain of the human signal recognition particle (SRP), 18 mutant SRP RNAs were constructed to disrupt Watson-Crick and G-U basepairs in helices 5, 6 and 8. Using a double-filter assay, the competitive binding of the mutant RNAs to purified human SRP68/72 or to a 7.4 kDa RNA-binding fragment of SRP72 (72frg) was measured. Binding of SRP68/72 was impaired by several mutations in the large domain with the most pronounced effects caused by changes in helix 5 (residues 222-231) and helix 8 (residues 176-191 and 202-214). Binding of the 72frg was diminished prominently by altering helix 5, in particular residues 120-128, and was unaffected by deleting helices 6 and 8. Deleting helix 8 diminished binding of SRP68/72 to a greater extent than deleting helix 6. The data suggest that nucleotide residues throughout most of the large SRP domain are directly and/or indirectly engaged in the binding of SRP68. In contrast, SRP72 binds only to a portion of the 5ef region.

Original languageEnglish (US)
Pages (from-to)154-159
Number of pages6
JournalRNA biology
Volume4
Issue number3
DOIs
StatePublished - Jan 1 2007
Externally publishedYes

Keywords

  • Protein targeting
  • Protein-RNA interactions
  • RNP assembly
  • SRP
  • Signal recognition particle
  • Site-directed mutagenesis

ASJC Scopus subject areas

  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Identification of the RNA binding regions of SRP68/72 and SRP72 by systematic mutagenesis of human SRP RNA'. Together they form a unique fingerprint.

  • Cite this