RNAi in Dictyostelium: The Role of RNA-directed RNA Polymerases and Double-stranded RNase
AUTOR(ES)
Martens, Henrik
FONTE
The American Society for Cell Biology
RESUMO
We show that in Dictyostelium discoideum an endogenous gene as well as a transgene can be silenced by introduction of a gene construct that is transcribed into a hairpin RNA. Gene silencing was accompanied by the appearance of sequence-specific RNA ∼23mers and seemed to have a limited capacity. The three Dictyostelium homologues of the RNA-directed RNA polymerase (RrpA, RrpB, and DosA) all contain an N-terminal helicase domain homologous to the one in the dicer nuclease, suggesting exon shuffling between RNA-directed RNA polymerase and the dicer homologue. Only the knock-out of rrpA resulted in a loss of the hairpin RNA effect and simultaneously in a loss of detectable ∼23mers. However, ∼23mers were still generated by the Dictyostelium dsRNase in vitro with extracts from rrpA−, rrpB−, and DosA− cells. Both RrpA and a target gene were required for production of detectable amounts of ∼23mers, suggesting that target sequences are involved in ∼23mer amplification.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=65640Documentos Relacionados
- RNA-directed RNA polymerases from healthy and from virus-infected cucumber.
- Identification of double-stranded RNA-binding domains in the interferon-induced double-stranded RNA-activated p68 kinase.
- A closely related group of RNA-dependent RNA polymerases from double-stranded RNA viruses.
- A deletion mutant of L-A double-stranded RNA replicates like M1 double-stranded RNA.
- Potential role of PKR in double-stranded RNA-induced macrophage activation
