PMID- 19494814
OWN - NLM
STAT- MEDLINE
DA  - 20090709 
DCOM- 20090902
IS  - 1476-4687 (Electronic)
VI  - 460
IP  - 7252
DP  - 2009 Jul 9
TI  - Uniparental expression of PolIV-dependent siRNAs in developing endosperm of
      Arabidopsis.
PG  - 283-6
AB  - Most eukaryotes produce small RNA (sRNA) mediators of gene silencing that bind
      to Argonaute proteins and guide them, by base pairing, to an RNA target.
      MicroRNAs (miRNAs) that normally target messenger RNAs for degradation or
      translational arrest are the best-understood class of sRNAs. However, in
      Arabidopsis thaliana flowers, miRNAs account for only 5% of the sRNA mass and
      less than 0.1% of the sequence complexity. The remaining sRNAs form a complex
      population of more than 100,000 different small interfering RNAs (siRNAs)
      transcribed from thousands of loci. The biogenesis of most of the siRNAs in
      Arabidopsis are dependent on RNA polymerase IV (PolIV), a homologue of
      DNA-dependent RNA polymerase II. A subset of these PolIV-dependent (p4)-siRNAs
      are involved in stress responses, and others are associated with epigenetic
      modifications to DNA or chromatin; however, the biological role is not known for
      most of them. Here we show that the predominant phase of p4-siRNA accumulation
      is initiated in the maternal gametophyte and continues during seed development.
      Expression of p4-siRNAs in developing endosperm is specifically from maternal
      chromosomes. Our results provide the first evidence for a link between genomic
      imprinting and RNA silencing in plants.
AD  - Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK.
FAU - Mosher Rebecca A 
AU  - Mosher RA 
FAU - Melnyk Charles W 
AU  - Melnyk CW 
FAU - Kelly Krystyna A 
AU  - Kelly KA 
FAU - Dunn Ruth M 
AU  - Dunn RM 
FAU - Studholme David J 
AU  - Studholme DJ 
FAU - Baulcombe David C
AU  - Baulcombe DC
LA  - eng
SI  - GEO/GSE15348
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20090603
PL  - England
TA  - Nature
JT  - Nature
JID - 0410462
RN  - 0(RNA, Plant)
RN  - 0(RNA, Small Interfering)
RN  - EC 2.7.7.-(RNA polymerase IV, Arabidopsis)
RN  - EC 2.7.7.6(
SB  - IM
MH  - Arabidopsis/*embryology/enzymology/*genetics
MH  - DNA-Directed RNA Polymerases/genetics/*metabolism
MH  - *Gene Expression Regulation, Plant
MH  - Genome, Plant/genetics
MH  - Genomic Imprinting
MH  - RNA Interference
MH  - RNA, Plant/biosynthesis/*genetics
MH  - RNA, Small Interfering/biosynthesis/*genetics
MH  - Seeds/embryology/enzymology/*genetics
EDAT- 2009/06/05 09:00
MHDA- 2009/09/03 06:00
CRDT- 2009/06/06 09:00
PHST- 2009/01/28 00:00[received]
PHST- 2009/04/21 00:00[accepted]
PHST- 2009/06/03 00:00[aheadofprint]
AID - nature08084[pii]
AID - 10.1038/nature08084[doi]
PST - ppublish
SO  - Nature. 2009 Jul9 ; 460(7252):283-6 Epub 2009 06 03.