Abstract
Previous work has suggested that de novo methylation of plant nuclear genes can be triggered by an RNA-DNA interaction. To test whether transcription of a promoter would induce de novo methylation and silencing of unlinked genes driven by the same promoter, a chimeric 'gene' consisting of a nopaline synthase promoter (NOSpro) positioned downstream of the cauliflower mosaic virus 35S promoter (35Spro) and flanked at the 3' end by a NOS terminator (NOSter) was constructed and introduced into the genome of a plant that normally expresses an unmethylated NOSpro-neomycinphosphotransferase (nptII) gene. Transformants were tested for kanamycin resistance and NOSpro RNA synthesis. Most produced a full-length polyadenylated NOSpro RNA, which did not induce silencing or methylation at the NOSpro-nptII target gene. One, however, contained truncated non-polyadenylated NOSpro RNA; in this plant, the NOSpro-nptII gene became silenced and methylated in the NOSpro region. Molecular analysis of the NOSpro silencing locus revealed two incomplete copies of the 35Spro-NOSpro gene arranged as an inverted repeat with NOSpro sequences at the center. Reducing NOSpro transcription by crossing a 35Spro-silencing locus partially reactivated nptII gene expression and decreased NOSpro methylation at the target locus, thus implicating aberrant NOSpro RNA in this trans-silencing phenomenon.
Full Text
The Full Text of this article is available as a PDF (406.8 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bender J. Cytosine methylation of repeated sequences in eukaryotes: the role of DNA pairing. Trends Biochem Sci. 1998 Jul;23(7):252–256. doi: 10.1016/s0968-0004(98)01225-0. [DOI] [PubMed] [Google Scholar]
- Bollmann J., Carpenter R., Coen E. S. Allelic interactions at the nivea locus of Antirrhinum. Plant Cell. 1991 Dec;3(12):1327–1336. doi: 10.1105/tpc.3.12.1327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Colot V., Maloisel L., Rossignol J. L. Interchromosomal transfer of epigenetic states in Ascobolus: transfer of DNA methylation is mechanistically related to homologous recombination. Cell. 1996 Sep 20;86(6):855–864. doi: 10.1016/s0092-8674(00)80161-0. [DOI] [PubMed] [Google Scholar]
- Depicker A., Montagu M. V. Post-transcriptional gene silencing in plants. Curr Opin Cell Biol. 1997 Jun;9(3):373–382. doi: 10.1016/s0955-0674(97)80010-5. [DOI] [PubMed] [Google Scholar]
- Furner I. J., Sheikh M. A., Collett C. E. Gene silencing and homology-dependent gene silencing in Arabidopsis: genetic modifiers and DNA methylation. Genetics. 1998 Jun;149(2):651–662. doi: 10.1093/genetics/149.2.651. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hobbs S. L., Warkentin T. D., DeLong C. M. Transgene copy number can be positively or negatively associated with transgene expression. Plant Mol Biol. 1993 Jan;21(1):17–26. doi: 10.1007/BF00039614. [DOI] [PubMed] [Google Scholar]
- Hollick J. B., Dorweiler J. E., Chandler V. L. Paramutation and related allelic interactions. Trends Genet. 1997 Aug;13(8):302–308. doi: 10.1016/s0168-9525(97)01184-0. [DOI] [PubMed] [Google Scholar]
- Ingelbrecht I., Van Houdt H., Van Montagu M., Depicker A. Posttranscriptional silencing of reporter transgenes in tobacco correlates with DNA methylation. Proc Natl Acad Sci U S A. 1994 Oct 25;91(22):10502–10506. doi: 10.1073/pnas.91.22.10502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jones A. L., Thomas C. L., Maule A. J. De novo methylation and co-suppression induced by a cytoplasmically replicating plant RNA virus. EMBO J. 1998 Nov 2;17(21):6385–6393. doi: 10.1093/emboj/17.21.6385. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Jorgensen R. A., Cluster P. D., English J., Que Q., Napoli C. A. Chalcone synthase cosuppression phenotypes in petunia flowers: comparison of sense vs. antisense constructs and single-copy vs. complex T-DNA sequences. Plant Mol Biol. 1996 Aug;31(5):957–973. doi: 10.1007/BF00040715. [DOI] [PubMed] [Google Scholar]
- Matzke A. J., Neuhuber F., Park Y. D., Ambros P. F., Matzke M. A. Homology-dependent gene silencing in transgenic plants: epistatic silencing loci contain multiple copies of methylated transgenes. Mol Gen Genet. 1994 Aug 2;244(3):219–229. doi: 10.1007/BF00285449. [DOI] [PubMed] [Google Scholar]
- Matzke M. A., Matzke A. J. Epigenetic silencing of plant transgenes as a consequence of diverse cellular defence responses. Cell Mol Life Sci. 1998 Jan;54(1):94–103. doi: 10.1007/s000180050128. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Matzke M. A., Primig M., Trnovsky J., Matzke A. J. Reversible methylation and inactivation of marker genes in sequentially transformed tobacco plants. EMBO J. 1989 Mar;8(3):643–649. doi: 10.1002/j.1460-2075.1989.tb03421.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Metzlaff M., O'Dell M., Cluster P. D., Flavell R. B. RNA-mediated RNA degradation and chalcone synthase A silencing in petunia. Cell. 1997 Mar 21;88(6):845–854. doi: 10.1016/s0092-8674(00)81930-3. [DOI] [PubMed] [Google Scholar]
- Meyer P., Saedler H. HOMOLOGY-DEPENDENT GENE SILENCING IN PLANTS. Annu Rev Plant Physiol Plant Mol Biol. 1996 Jun;47(NaN):23–48. doi: 10.1146/annurev.arplant.47.1.23. [DOI] [PubMed] [Google Scholar]
- Montgomery M. K., Fire A. Double-stranded RNA as a mediator in sequence-specific genetic silencing and co-suppression. Trends Genet. 1998 Jul;14(7):255–258. doi: 10.1016/s0168-9525(98)01510-8. [DOI] [PubMed] [Google Scholar]
- Odell J., Caimi P., Sauer B., Russell S. Site-directed recombination in the genome of transgenic tobacco. Mol Gen Genet. 1990 Sep;223(3):369–378. doi: 10.1007/BF00264442. [DOI] [PubMed] [Google Scholar]
- Park Y. D., Papp I., Moscone E. A., Iglesias V. A., Vaucheret H., Matzke A. J., Matzke M. A. Gene silencing mediated by promoter homology occurs at the level of transcription and results in meiotically heritable alterations in methylation and gene activity. Plant J. 1996 Feb;9(2):183–194. doi: 10.1046/j.1365-313x.1996.09020183.x. [DOI] [PubMed] [Google Scholar]
- Pfeifer K., Tilghman S. M. Allele-specific gene expression in mammals: the curious case of the imprinted RNAs. Genes Dev. 1994 Aug 15;8(16):1867–1874. doi: 10.1101/gad.8.16.1867. [DOI] [PubMed] [Google Scholar]
- Steger G., Tabler M., Brüggemann W., Colpan M., Klotz G., Sänger H. L., Riesner D. Structure of viroid replicative intermediates: physico-chemical studies on SP6 transcripts of cloned oligomeric potato spindle tuber viroid. Nucleic Acids Res. 1986 Dec 22;14(24):9613–9630. doi: 10.1093/nar/14.24.9613. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tanzer M. M., Thompson W. F., Law M. D., Wernsman E. A., Uknes S. Characterization of Post-Transcriptionally Suppressed Transgene Expression That Confers Resistance to Tobacco Etch Virus Infection in Tobacco. Plant Cell. 1997 Aug;9(8):1411–1423. doi: 10.1105/tpc.9.8.1411. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Thangavelu M., Belostotsky D., Bevan M. W., Flavell R. B., Rogers H. J., Lonsdale D. M. Partial characterization of the Nicotiana tabacum actin gene family: evidence for pollen-specific expression of one of the gene family members. Mol Gen Genet. 1993 Aug;240(2):290–295. doi: 10.1007/BF00277069. [DOI] [PubMed] [Google Scholar]
- Turker M. S., Bestor T. H. Formation of methylation patterns in the mammalian genome. Mutat Res. 1997 Apr;386(2):119–130. doi: 10.1016/s1383-5742(96)00048-8. [DOI] [PubMed] [Google Scholar]
- Wassenegger M., Heimes S., Riedel L., Sänger H. L. RNA-directed de novo methylation of genomic sequences in plants. Cell. 1994 Feb 11;76(3):567–576. doi: 10.1016/0092-8674(94)90119-8. [DOI] [PubMed] [Google Scholar]
- Wassenegger M., Pélissier T. A model for RNA-mediated gene silencing in higher plants. Plant Mol Biol. 1998 May;37(2):349–362. doi: 10.1023/a:1005946720438. [DOI] [PubMed] [Google Scholar]