Lower levels of transgene silencing in roots is associated with reduced DNA methylation levels at non-symmetrical sites but not at symmetrical sites

Andika Ida Bagus, Hideki Kondo, Muhammad Danial Rahim, Tetsuo Tamada

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Transgene transcripts were recently shown to accumulate at higher levels in roots, relative to leaves, of silenced-transgenic Nicotiana benthamiana plants and to be inversely related with the accumulation of small interfering RNAs (siRNAs), suggesting that RNA silencing is less active in roots than in leaves (Andika et al., 2005. Mol. Plant-Microbe Interact. 18: 194). Here we show that the lower transgene RNA silencing activity in roots was associated with lower transgene methylation levels at non-symmetrical CpNpN context but not at symmetrical CpG or CpNpG context in three sets of transformant plants with different exogenous genes. In contrast, such a difference between roots and leaves was not observed for the Tnt1 retrotransposon: no Tnt1 transcript was detected in roots or in leaves of N. benthamiana, while equal levels of Tnt1-derived siRNA accumulation and Tnt1 methylation were found. From our data and previously reported information, we suggest that roots have less of an activity that acts at the step of generation of siRNAs.

Original languageEnglish
Pages (from-to)423-435
Number of pages13
JournalPlant Molecular Biology
Volume60
Issue number3
DOIs
Publication statusPublished - Feb 2006

Fingerprint

DNA methylation
DNA Methylation
Transgenes
Small Interfering RNA
transgenes
Methylation
RNA Interference
small interfering RNA
RNA
Retroelements
Nicotiana benthamiana
RNA interference
methylation
Tobacco
leaves
Genes
retrotransposons
genetically modified organisms
microorganisms
genes

Keywords

  • DNA methylation
  • RNA silencing
  • Root tissue
  • Transposon silencing

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Biochemistry

Cite this

Lower levels of transgene silencing in roots is associated with reduced DNA methylation levels at non-symmetrical sites but not at symmetrical sites. / Ida Bagus, Andika; Kondo, Hideki; Rahim, Muhammad Danial; Tamada, Tetsuo.

In: Plant Molecular Biology, Vol. 60, No. 3, 02.2006, p. 423-435.

Research output: Contribution to journalArticle

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