2l6m
Structure of C-terminal dsRBD of the Fission Yeast DICER (Dcr1)Structure of C-terminal dsRBD of the Fission Yeast DICER (Dcr1)
Structural highlights
FunctionDCR1_SCHPO Required for G1 arrest and mating in response to nitrogen starvation. Ago1 regulation of cytokinesis and cell cycle checkpoints occurs downstream of dcr1. Required, indirectly, for regulated hyperphosphorylation of cdc2. Has a role in the RNA interference (RNAi) pathway which is important for heterochromatin formation, accurate chromosome segregation, centromere cohesion and telomere function during mitosis and meiosis. Digests double-stranded RNA (dsRNA) producing 21 to 23 bp dsRNAs, so-called interfering RNAs (siRNA). Required for both post-transcriptional and transcriptional gene silencing. Required for silencing at the centromeres and for initiation of transcriptionally silent heterochromatin at the mating type locus. Promotes histone H3 'Lys-10' methylation necessary for centromere function. Required for recruitment of swi6 and cohesin to an ectopic dg repeat. Publication Abstract from PubMedDicer proteins function in RNA interference (RNAi) pathways by generating small RNAs (sRNAs). Here, we report the solution structure of the C-terminal domain of Schizosaccharomyces pombe Dicer (Dcr1). The structure reveals an unusual double-stranded RNA binding domain (dsRBD) fold embedding a novel zinc-binding motif that is conserved among dicers in yeast. Although the C-terminal domain of Dcr1 still binds nucleic acids, this property is dispensable for proper functioning of Dcr1. In contrast, disruption of zinc coordination renders Dcr1 mainly cytoplasmic and leads to remarkable changes in gene expression and loss of heterochromatin assembly. In summary, our results reveal novel insights into the mechanism of nuclear retention of Dcr1 and raise the possibility that this new class of dsRBDs might generally function in nucleocytoplasmic trafficking and not substrate binding. The C-terminal domain of Dcr1 constitutes a novel regulatory module that might represent a potential target for therapeutic intervention with fungal diseases. An extended dsRBD with a novel zinc-binding motif mediates nuclear retention of fission yeast Dicer.,Barraud P, Emmerth S, Shimada Y, Hotz HR, Allain FH, Buhler M EMBO J. 2011 Aug 16;30(20):4223-35. doi: 10.1038/emboj.2011.300. PMID:21847092[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
|