Gene silencing in Neurospora crassa requires a protein homologous to RNA-dependent RNA polymerase

Nature ◽  
10.1038/20215 ◽  
1999 ◽  
Vol 399 (6732) ◽  
pp. 166-169 ◽  
Author(s):  
Carlo Cogoni ◽  
Giuseppe Macino
2005 ◽  
Vol 149 (1) ◽  
pp. 111-115 ◽  
Author(s):  
Minni R.L. Laurila ◽  
Paula S. Salgado ◽  
Eugene V. Makeyev ◽  
Joanne Nettelship ◽  
David I. Stuart ◽  
...  

2018 ◽  
Author(s):  
Miguel Vasconcelos Almeida ◽  
Sabrina Dietz ◽  
Stefan Redl ◽  
Emil Karaulanov ◽  
Andrea Hildebrandt ◽  
...  

AbstractIn every domain of life, Argonaute proteins and their associated small RNAs regulate gene expression. Despite great conservation of Argonaute proteins throughout evolution, many proteins acting in small RNA pathways are not widely conserved. Gametocyte-specific factor 1 (Gtsf1) proteins, characterized by two tandem CHHC zinc fingers and an unstructured, acidic C-terminal tail, are conserved in animals and act in small RNA pathways. In fly and mouse, they are required for fertility and have been shown to interact with Piwi clade Argonautes. We identified T06A10.3 as the Caenorhabditis elegans Gtsf1 homolog and named it gtsf-1. Given its conserved nature and roles in Piwi-mediated gene silencing, we sought out to characterize GTSF-1 in the context of the small RNA pathways of C. elegans. Like its homologs, GTSF-1 is required for normal fertility. Surprisingly, we report that GTSF-1 is not required for Piwi-mediated gene silencing. Instead, gtsf-1 mutants show strong depletion of a class of endogenous small RNAs, known as 26G-RNAs, and fully phenocopy mutants lacking RRF-3, the RNA-dependent RNA Polymerase that synthesizes 26G-RNAs. We show, both in vivo and in vitro, that GTSF-1 specifically and robustly interacts with RRF-3 via its tandem CHHC zinc fingers. Furthermore, we demonstrate that GTSF-1 is required for the assembly of a larger RRF-3 and DCR-1-containing complex, also known as ERIC, thereby allowing for 26G-RNA generation. We propose that GTSF-1 homologs may similarly act to drive the assembly of larger complexes that subsequently act in small RNA production and/or in imposing small RNA-mediated silencing activities.


2015 ◽  
Author(s):  
Angel Emilio Martínez de Alba ◽  
Ana Moreno ◽  
Marc Gabriel ◽  
Allison C Mallory ◽  
Aurélie Christ ◽  
...  

Cytoplasmic degradation of endogenous RNAs is an integral part of RNA quality control (RQC) and often relies on the removal of the 5’ cap structure and their subsequent 5’ to 3’ degradation in cytoplasmic processing (P-)bodies. In parallel, many eukaryotes degrade exogenous and selected endogenous RNAs through post-transcriptional gene silencing (PTGS). In plants, PTGS depends on small interfering (si)RNAs produced after the conversion of single-stranded RNAs to doublestranded RNAs by the cellular RNA DEPENDENT RNA POLYMERASE 6 (RDR6) in cytoplasmic siRNA-bodies. PTGS and RQC compete for transgene-derived RNAs, but it is unknown whether this competition also occurs for endogenous transcripts. We show that the lethality of decapping mutants is suppressed by impairing RDR6 activity. We establish that upon decapping impairment hundreds of endogenous mRNAs give rise to a new class of rqc-siRNAs, that over-accumulate when RQC processes are impaired, a subset of which depending on RDR6 for their production. We observe that P- and siRNA-bodies often are dynamically juxtaposed, potentially allowing for crosstalk of the two machineries. Our results suggest that the decapping of endogenous RNA limits their entry into the PTGS pathway. We anticipate that the rqc-siRNAs identified in decapping mutants represent a subset of a larger ensemble of endogenous siRNAs.


2013 ◽  
Vol 35 (3) ◽  
pp. 202-209 ◽  
Author(s):  
Rikno Harmoko ◽  
Wahyu Indra Duwi Fanata ◽  
Jae Yong Yoo ◽  
Ki Seong Ko ◽  
Yeong Gil Rim ◽  
...  

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