Sequence-specific RNA binding mediated by the RNase PH domain of components of the exosome.
We have previously demonstrated that PM-Scl-75, a component of the human exosome complex involved in RNA maturation and mRNA decay, can specifically interact with RNAs containing an AU-rich instability element. Through the analysis of a series of deletion mutants, we have now shown that a 266 amino acid fragment representing the RNase PH domain is responsible for the sequence-specific binding to AU-rich elements. Furthermore, we found that the RNase PH domains from two other exosomal components, OIP2 and RRP41, as well as from Escherichia coli polynucleotide phosphorylase, are all capable of specifically interacting with RNAs containing an AU-rich element with similar affinities. Finally, we demonstrate that the interaction of the RNase PH domain of PM-Scl-75 is readily competed by poly(U), but only inefficiently using other homopolymeric RNAs. These data demonstrate that RNase PH domains in general have an affinity for U- and AU-rich sequences, and broaden the potential role in RNA biology of proteins containing these domains.
Anderson
John R
JR
Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado 80523, USA.
Mukherjee
Devi
D
Muthukumaraswamy
Karthika
K
Moraes
Karen C M
KC
Wilusz
Carol J
CJ
Wilusz
Jeffrey
J
D001482:Base Composition; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D005095:Exoribonucleases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D066298:In Vitro Techniques; D010957:Plasmids / Q000235:genetics; D011072:Poly U / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012313:RNA / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D020871:RNA Stability; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion
D011994:Recombinant Proteins; D011072:Poly U; D012313:RNA; C056502:ribonuclease PH; D005095:Exoribonucleases