Take our Survey

Reference: Nichols M, et al. (1988) Yeast RNase P: catalytic activity and substrate binding are separate functions. Proc Natl Acad Sci U S A 85(5):1379-83

Reference Help

Abstract


During tRNA biosynthesis the 5'-leader sequences in precursor tRNAs are removed by the ribonucleoprotein RNase P, an enzyme whose RNA moiety is required for activity. To clarify some aspects of the enzyme mechanism, we examined substrate binding and product formation with mutant precursor tRNAs. Mutations G-1----A or U-2----C in the Schizosaccharomyces pombe sup3-e tRNASer, which cause mispairing at or near the top of the acceptor stem, prevent the removal of the 5'-leader sequences by Saccharomyces cerevisiae RNase P. Equilibrium binding studies involving specific gel retardation of RNase P-precursor tRNA complexes showed that complexes with wild-type and A-1 and C-2 mutant precursor tRNAs had very similar dissociation constants (average Kd for sup3 = 1.5 +/- 0.2 nM). Thus, the 5'-terminal nucleotides of mature tRNA, on the 3' proximal side of the RNase P cleavage site, affect the enzyme's catalytic function but not substrate binding. The catalytic integrity of the RNA component of RNase P is not essential for binding of tRNA precursors, as demonstrated by gel retardation of micrococcal nuclease-inactivated enzyme. This suggests a possible role for the protein component of the enzyme in substrate binding. Upon restoration of base pairing to the acceptor stem in the A-1 or C-2 mutants, we found that, in addition to a requirement for pairing at these positions, conservation of the wild-type first and second nucleotides of the tRNA was necessary to obtain maximal cleavage by RNase P. This indicates a distinct sequence preference of this enzyme.

Reference Type
Journal Article | Research Support, U.S. Gov't, P.H.S.
Authors
Nichols M, Soll D, Willis I
Primary Lit For
Additional Lit For
Review For

Interaction Annotations


Increase the total number of rows showing on this page by using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details about experiment type and any other genes involved in the interaction.

Interactor Interactor Type Assay Annotation Action Modification Phenotype Source Reference

Gene Ontology Annotations


Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table.

Gene Gene Ontology Term Qualifier Aspect Method Evidence Source Assigned On Annotation Extension Reference

Phenotype Annotations


Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details.

Gene Phenotype Experiment Type Mutant Information Strain Background Chemical Details Reference

Regulation Annotations


Increase the total number of rows displayed on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; to filter the table by a specific experiment type, type a keyword into the Filter box (for example, “microarray”); download this table as a .txt file using the Download button or click Analyze to further view and analyze the list of target genes using GO Term Finder, GO Slim Mapper, SPELL, or YeastMine.

Regulator Target Experiment Assay Construct Conditions Strain Background Reference