Dataset Information

GTSF-1 is required for the formation of an RNA-dependent RNA Polymerase complex in C. elegans

ABSTRACT: In every domain of life, Argonaute proteins and their associated small RNAs regulate gene expression. Despite great conservation of Argonaute proteins throughout evolution, there are not many other conserved proteins involved in small RNA pathways. Gametocyte-specific factor 1 (Gtsf1) proteins, characterized by two tandem CHHC zinc fingers and an unstructured, acidic C-terminal tail, represent one such conserved small RNA pathway component. 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 lack 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.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Caenorhabditis Elegans

SUBMITTER: F Butter

LAB HEAD: Falk Butter

PROVIDER: PXD007665 | Pride | 2018-05-11

REPOSITORIES: Pride

ACCESS DATA

Similar Datasets

Project description:Epigenetic inheritance is the transmission of information independently of the nucleotide sequence of the genome. A fundamental question in biology is to what extent does epigenetics contribute to trans-generational inheritance. Here we investigate the role of Argonaute-small-RNA pathways in epigenetic inheritance in the nematode C. elegans. Argonautes present their guide RNAs for base-pairing with target sequences and, upon binding, can cleave the target RNA and/or recruit cofactors that mediate post-transcriptional or transcriptional silencing 1,2. Previous studies have shown that Argonaute small-RNA pathways reinforce and maintain epigenetic silencing in C. elegans 3-5. For example, the conserved PIWI-related Argonaute PRG-1 initiates a remarkably stable mode of epigenetic silencing, termed RNA-induced epigenetic silencing (RNAe) 3. Alleles that are silenced by RNAe send trans-acting Argonaute-small-RNA signals that can act in a sequence-specific manner to induce the permanent Epigenetic inheritance is the transmission of information independently of the nucleotide sequence of the genome. A fundamental question in biology is to what extent does epigenetics contribute to trans-generational inheritance. Here we investigate the role of Argonaute-small-RNA pathways in epigenetic inheritance in the nematode C. elegans. Argonautes present their guide RNAs for base-pairing with target sequences and, upon binding, can cleave the target RNA and/or recruit cofactors that mediate post-transcriptional or transcriptional silencing 1,2. Previous studies have shown that Argonaute small-RNA pathways reinforce and maintain epigenetic silencing in C. elegans 3-5. For example, the conserved PIWI-related Argonaute PRG-1 initiates a remarkably stable mode of epigenetic silencing, termed RNA-induced epigenetic silencing (RNAe) 3. Alleles that are silenced by RNAe send trans-acting Argonaute-small-RNA signals that can act in a sequence-specific manner to induce the permanent silencing of homologous genes 3. Here we explore an opposite phenomenon, RNA-induced gene activation (RNAa), in which an expressed gene provides a sequence-specific signal that can activate a silent homologous gene. We provide evidence that the CSR-1 Argonaute is required for this trans-activating signal. CSR-1 engages antisense small RNAs complementary to most, if not all, germline-expressed mRNAs 6,7. Moreover, we show that the ability of a foreign sequence to mediate RNAa is correlated with acquisition of CSR-1-associated small RNAs targeting the foreign sequence. Thus CSR-1 small RNAs constitute a memory of previous germline-gene expression that protects endogenous genes from epigenetic silencing. These findings reveal a remarkably sophisticated epigenetic surveillance mechanism that monitors the flow of transgenerational information ensuring that progeny express only those genes also expressed in their parents. Examine small RNA population changes in different transgene lines

Dataset Information

GTSF-1 is required for the formation of an RNA-dependent RNA Polymerase complex in C. elegans

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure