Position effects and epigenetic silencing of plant transgenes

Current Opinion in Plant Biology

Volumn 1, Issue 2, 1998, Pages 142-148

  Matzke, Antonius J M ^a   Matzke, Marjori A ^a  

^a ERICH SCHMID INSTITUTE OF MATERIALS SCIENCE   (Austria)

Author keywords

[No Author keywords available]

Indexed keywords

CYTOSINE; PLANT DNA;

DNA METHYLATION; GENE EXPRESSION REGULATION; METABOLISM; REGULATOR GENE; REVIEW; STRUCTURE ACTIVITY RELATION; TRANSGENE; TRANSGENIC PLANT;

CYTOSINE; DNA METHYLATION; DNA, PLANT; GENE EXPRESSION REGULATION, PLANT; GENES, SWITCH; PLANTS, GENETICALLY MODIFIED; STRUCTURE-ACTIVITY RELATIONSHIP; TRANSGENES;

EID: 0032035334     PISSN: 13695266     EISSN: None     Source Type: Journal    
DOI: 10.1016/S1369-5266(98)80016-2     Document Type: Article

References (14)

1. Cerutti H, Johnson A, Gillham N, Boynton J: Epigenetic silencing of a foreign gene in nuclear transformants of Chlamydomonas. Plant Cell 1997, 9:925-945. This is the first report of epigenetic silencing of a transgene in a green alga. As has been observed with other epigenetic phenomena in genetically identical single cells [50] intermediate expression states were observed, and completely silenced states were mitotically and meiotically heritable. Most notably, neither methylation nor large alterations in chromatin structure were correlated with silencing, indicating a role for alternative forms of heritable inactivation yet to be identified (see also [5**]).
2. Angell S, Baulcombe D: Consistent gene silencing in transgenic plants expressing a replicating potato virus X RNA. EMBO J 1997, 16:3675-3684.
3. Meyer P, Saedler H: Homology-dependent gene silencing in plants. Annu Rev Plant Physiol Plant Mol Biol 1996, 47:23-48.
4. Matzke M, Matzke A, Eggleston W: Transgene silencing and paramutation: a common response to invasive DNA? Trends Plant Sci 1996, 1:382-388. Striking similarities between frans-silencing involving transgene loci containing homologous promoters and paramutation at the r locus in maize are detailed. The presence of highly homologous doppia transposable elements in the promoters of the copies of r genes participating in paramutation together with the obvious invasive nature of transgenes involved in trans-silencing led to the proposition that both reflect a host response to foreign DNA (see also [48**]).
5. Hollick J, Dorweiler J, Chandler V: Paramutation and related allelic interactions. Trends Genet 1997, 13:302-307. Different paramutation systems are described, including those involving unlinked transgene loci, and various possible mechanisms are discussed.
6. Depicker A, Van Montagu M: Post-transcriptional gene silencing in plants. Curr Opin Cell Biol 1997, 9:373-382. This review is devoted to the post-transcriptional mode of gene silencing in transgenic plants and includes natural examples that effect endogenous genes. Possible mechanisms involving various hypothetical RNA species are thoroughly described.
7. Stam M, Mol J, Kooter J: The silence of genes in transgenic plants. Ann Botany 1997, 79:3-12.
8. Matzke M, Matzke A: Epigenetic silencing of plant transgenes as a consequence of diverse cellular defense responses. Cell Mol Life Sci 1998, in press.
9. Richards E: DNA methylation and plant development Trends Genet 1997, 13:31-322.
10. Finnegan E, Genger R, Peacock W, Dennis E: DNA methylation in plants. Annu Rev Plant Physiol Plant Mol Biol 1998, 49:in press.
11. Paszkowski J, Mittelsten-Scheid O: Plants: the genetics of epigenetics Curr Biol 1998, in press.
12. Yoder J, Walsh C, Bestor T: Cytosine methylation and the ecology of intragenomic parasites. Trends Genet 1997, 13:335-339. The authors promote the heretical view that methylation has nothing to do with the developmental regulation of gene expression; instead, the primary function of methylation is to inactivate transposable elements, which comprise a large fraction of the methylated cytosines in vertebrate genomes, with important secondary roles in X-chromosome inactivation and parental imprinting. The argument is compelling and should refocus the discussion on cytosine methylation in higher eukaryotes.
13. Bennetzen J: The contributions of retroelements to plant genome organization, function and evolution. Trends Microbiol 1996, 4:347-353.
14. Wessler S, Bureau T, White S: LTR-retrotransposons and MITEs: important players in the evolution of plant genomes. Curr Opin Genet Dev 1995, 5:814-821.