Transgene-induced gene silencing in plants.

摘要: The recent development of gene transfer methods for almost all eukaryotes has revealed that transgenes can undergo silencing after integration in the genome. Host genes also be silenced as a consequence presence homologous transgene, thus limiting potential application genetic transformation. Despite this limitation, transgene-induced events were considered originally anecdotal phenomena. However, more and similarities found between natural epigenetic phenomena, considerable interest been devoted to subject (for reviews see Depicker Van Montagu, 1997; Stam et al., 1997b). Epigenetics is commonly defined ‘the study mitotically and/or meiotically heritable changes function cannot explained by its DNA sequence’ (Russo 1996). For long time, was only target modifications. Epigenetic corresponding chromatin structure affecting transcription have reported eukaryotes: yeast, fungi, Drosophila, plants mammals (Dorer, Foss Selker, 1991; Rossignol Faugeron, 1994; Ye Signer, studies suggested that, besides DNA, other molecules modified manner resembles changes. First, it shown proteins converted into aberrant conformation called prions yeast (Lacroute, 1971; Prusiner, 1982). More recently, involvement RNA hypothesized explain post-transcriptional plants, fungi nematodes (Cogoni 1996; Fire 1998; Napoli 1990). This review will focus on phenomena plants. number copies transgene integrate genome transformed plant