Triggering of a plant molecular defense mechanism: Increase in gene expression levels of transgenegshI and poplar genegsh1 (Populus×canescens) by response to the DNA demethylating drug DHAC — an qRT-PCR analysis

Abstract

As DNA methylation patterns are inherited (‘epigenetic memory’) gsh I transgenic poplar ( Populus × canescens ) clones (11 ggs and 6 Lgl ) were treated with the DNA demethylating drug DHAC (5,6-dihydro-5′-azacytidine hydrochloride) at 10 −4 M for 7 days in order to study acquired plant molecular defense mechanisms in novel plant sources. In this study, the response of relative gene expression levels of transgene gsh I and poplar gene gsh 1 to DHAC treatment were analyzed by qRT-PCR ( q uantitative r everse t ranscriptase PCR). High expression levels of transgene gsh I were observed in the 6 Lgl clone (13.5-fold increase) compared to 11 ggs (1.0) sample. The expression level doubled (1.8-fold increase) in the DHAC-treated 6 Lgl samples but not in the 11 ggs clone (0.4-fold). Contrary to this, the relative copy number of transgene gsh I in the 6 Lgl clone was found to be 60% less (1.0) than in the 11 ggs sample (1.6). Relative expression level of endogenous poplar gene gsh 1 showed significantly higher resp...