Details

Autor(en) / Beteiligte

• Martens, Henrik
• Novotny, Jindrich
• Oberstrass, Jürgen
• Steck, Theodore L
• Postlethwait, Pamela
• Nellen, Wolfgang
• Devreotes, Peter N.

Titel

RNAi in Dictyostelium: the role of RNA-directed RNA polymerases and double-stranded RNase

Ist Teil von

• Molecular biology of the cell, 2002-02, Vol.13 (2), p.445-453

Ort / Verlag

United States: The American Society for Cell Biology

Erscheinungsjahr

2002

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• 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 about 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 about 23mers. However, about 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 about 23mers, suggesting that target sequences are involved in about 23mer amplification.