The first phytoplasma RNase P RNA provides new insights into the sequence requirements of this ribozyme
AUTOR(ES)
Wagner, Matthias
FONTE
Oxford University Press
RESUMO
A high variability of RNase P RNA structures is seen among members of the Mycoplasma group. To gain further insight into the structure–function relations of this ribozyme, we have searched for the RNase P RNA gene from more distant relatives, the phytoplasmas. These mycoplasma-like organisms are the aetiological agents of many severe plant diseases. We report the sequence and catalytic properties of RNase P RNA from the phytoplasma causing apple proliferation disease. The primary and postulated secondary structure of this 443 nt long RNA are most similar to those of Acholeplasma, supporting the phylogenetic position of this pathogen. Remarkably, the extremely AT-rich (73.6%) phytoplasma RNA differs from the known bacterial consensus sequence by a single base pair, which is positioned close to the substrate cleavage site in current three-dimensional models. Phytoplasma RNase P RNA functions as an efficient ribozyme in vitro. Conversion of its sequence to the full consensus and kinetic analysis of the resulting mutant RNAs suggests that neither the sequence alone, nor the type of pairing at this position is crucial for substrate binding or catalysis by the RNase P ribozyme. These results refine the bacterial consensus structure close to the catalytic core and thus improve our understanding of RNase P RNA function.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=55747Documentos Relacionados
- Fusion-protein truncation provides new insights into leukemogenesis
- Yeast mitochondrial RNase P RNA synthesis is altered in an RNase P protein subunit mutant: insights into the biogenesis of a mitochondrial RNA-processing enzyme.
- Ancient DNA Provides New Insights into the Evolutionary History of New Zealand's Extinct Giant Eagle
- Comparative Genomic Hybridization Provides New Insights Into the Molecular Taxonomy of the Saccharomyces Sensu Stricto Complex
- Conditional switching of VEGF provides new insights into adult neovascularization and pro-angiogenic therapy