AGO1, QDE-2, and RDE-1 are related proteins required for post-transcriptional gene silencing in plants, quelling in fungi, and RNA interference in animals
M. Fagard et al., AGO1, QDE-2, and RDE-1 are related proteins required for post-transcriptional gene silencing in plants, quelling in fungi, and RNA interference in animals, P NAS US, 97(21), 2000, pp. 11650-11654
Citations number
46
Categorie Soggetti
Multidisciplinary
Journal title
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
Introduction of transgene DNA may lead to specific degradation of RNAs that
are homologous to the transgene transcribed sequence through phenomena nam
ed post-transcriptional gene silencing (PTGS) in plants, quelling in fungi,
and RNA interference (RNAi) in animals. It was shown previously that PTGS.
quelling, and RNAi require a set of related proteins (SCS2, QDE-1, and EGO
-1, respectively). Here we report the isolation of Arabidopsis mutants impa
ired in PTGS which are affected at the Argonaote1 (AGO1) locus. AGO1 is sim
ilar to QDE-2 required for quelling and RDE-1 required for RNAi. Sequencing
of ago1 mutants revealed one amino acid essential for PTGS that is also pr
esent in QDE-2 and RDE-1 in a highly conserved motif. Taken together, these
results confirm the hypothesis that these processes derive from a common a
ncestral mechanism that controls expression of invading nucleic acid molecu
les at the post-transcriptional level. As opposed to rde-1 and qde-2 mutant
s, which are viable, ago1 mutants display several developmental abnormaliti
es, including sterility. These results raise the possibility that PTGS. or
at least some of its elements, could participate in the regulation of gene
expression during development in plants.