Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7355
pubmed:dateCreated
2011-7-14
pubmed:databankReference
pubmed:abstractText
A hallmark of RNA silencing is a class of approximately 22-nucleotide RNAs that are processed from double-stranded RNA precursors by Dicer. Accurate processing by Dicer is crucial for the functionality of microRNAs (miRNAs). The current model posits that Dicer selects cleavage sites by measuring a set distance from the 3' overhang of the double-stranded RNA terminus. Here we report that human Dicer anchors not only the 3' end but also the 5' end, with the cleavage site determined mainly by the distance (?22 nucleotides) from the 5' end (5' counting rule). This cleavage requires a 5'-terminal phosphate group. Further, we identify a novel basic motif (5' pocket) in human Dicer that recognizes the 5'-phosphorylated end. The 5' counting rule and the 5' anchoring residues are conserved in Drosophila Dicer-1, but not in Giardia Dicer. Mutations in the 5' pocket reduce processing efficiency and alter cleavage sites in vitro. Consistently, miRNA biogenesis is perturbed in vivo when Dicer-null embryonic stem cells are replenished with the 5'-pocket mutant. Thus, 5'-end recognition by Dicer is important for precise and effective biogenesis of miRNAs. Insights from this study should also afford practical benefits to the design of small hairpin RNAs.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1476-4687
pubmed:author
pubmed:copyrightInfo
©2011 Macmillan Publishers Limited. All rights reserved
pubmed:issnType
Electronic
pubmed:day
14
pubmed:volume
475
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
201-5
pubmed:meshHeading
pubmed-meshheading:21753850-Amino Acid Sequence, pubmed-meshheading:21753850-Animals, pubmed-meshheading:21753850-Base Sequence, pubmed-meshheading:21753850-Binding Sites, pubmed-meshheading:21753850-DEAD-box RNA Helicases, pubmed-meshheading:21753850-Drosophila Proteins, pubmed-meshheading:21753850-Embryonic Stem Cells, pubmed-meshheading:21753850-Evolution, Molecular, pubmed-meshheading:21753850-Giardia, pubmed-meshheading:21753850-HEK293 Cells, pubmed-meshheading:21753850-Humans, pubmed-meshheading:21753850-MicroRNAs, pubmed-meshheading:21753850-Molecular Sequence Data, pubmed-meshheading:21753850-Mutant Proteins, pubmed-meshheading:21753850-Mutation, pubmed-meshheading:21753850-Phosphates, pubmed-meshheading:21753850-Phosphorylation, pubmed-meshheading:21753850-RNA Helicases, pubmed-meshheading:21753850-Ribonuclease III, pubmed-meshheading:21753850-Substrate Specificity
pubmed:year
2011
pubmed:articleTitle
Dicer recognizes the 5' end of RNA for efficient and accurate processing.
pubmed:affiliation
School of Biological Sciences, Seoul National University, Seoul 151-742, Korea.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural