| 释义 |
- References
{{Technical|date=May 2010}}RNA-directed DNA methylation (RdDM) is an epigenetic process first discovered in plants (Wassenegger et al, 1994, Cell, Vol 76, 567-576). During RdDM, double-stranded RNAs (dsRNAs) are processed to 21-24 nucleotide small interfering RNAs (siRNAs) and guide methylation of homologous DNA loci. In plants dsRNAs may be generated from four sources: - Viral replication intermediates
- Products of the endogenous RNA-directed RNA polymerase
- Transcribed inverted repeats
- Transposable elements
Besides RNA molecules, a plethora of proteins are involved in the establishment of RdDM, like Argonautes, DNA methyltransferases, chromatin remodelling complexes. and the plant-specific Polymerase IV and Polymerase V. All these act in concert to add a methyl-group at the 5' position of cytosines. In contrast to animals, cytosines at all sequence context (CG, CHG, CHH) may get de novo methylated in plants. References- {{cite journal |doi=10.1016/0092-8674(94)90119-8 |title=RNA-directed de novo methylation of genomic sequences in plants |year=1994 |last1=Wassenegger |first1=Michael |last2=Heimes |first2=Sabine |last3=Riedel |first3=Leonhard |last4=Sänger |first4=Heinz L. |journal=Cell |volume=76 |issue=3 |pages=567–76 |pmid=8313476}}
- {{cite journal |doi=10.1038/nrg2719 |title=Establishing, maintaining and modifying DNA methylation patterns in plants and animals |year=2010 |last1=Law |first1=Julie A. |last2=Jacobsen |first2=Steven E. |journal=Nature Reviews Genetics |volume=11 |issue=3 |pages=204–20 |pmid=20142834 |pmc=3034103}}
- {{cite journal |doi=10.1038/nrm3152 |title=Multisubunit RNA polymerases IV and V: Purveyors of non-coding RNA for plant gene silencing |year=2011 |last1=Haag |first1=Jeremy R. |last2=Pikaard |first2=Craig S. |journal=Nature Reviews Molecular Cell Biology |volume=12 |issue=8 |pages=483–92 |pmid=21779025}}
- {{cite journal |doi=10.1016/j.cub.2012.04.010 |title=RNA-Directed DNA Methylation: Getting a Grip on Mechanism |year=2012 |last1=Bender |first1=Judith |journal=Current Biology |volume=22 |issue=10 |pages=R400–1 |pmid=22625855}}
- {{cite journal |doi=10.4161/rna.23542 |title=Revisiting RNA-directed DNA methylation |year=2013 |last1=Dalakouras |first1=Athanasios |last2=Wassenegger |first2=Michael |journal=RNA Biology |volume=10 |issue=3 |pages=453–5 |pmid=23324611 |pmc=3672289}}
{{DEFAULTSORT:Rna-Directed Dna Methylation}} 1 : Nucleic acids |