A cDNA fragment corresponding to deoxyhy-pusine synthase gene NbDHS was isolated and cloned into potato virus X (PVX) vector for functional analysis in Nico-tiana benthamiana by using virus-induced gene silencing (VIGS). Plants agroinfected with recombinant virus vector PVX-NbDHS exhibited an increase in leaf biomass, delay in natural leaf senescence and flowering time, and decrease in leaf chlorophyll content. Semi-quantitative RT-PCR and Northern analysis showed that the transcript level of DHS was significantly lower in PVX-NbDHS infected plants. At the same time, the expression for eIF-5A, the target proteins of DHS in N. benthamiana, was concomitantly suppressed by semi-quantitative RT-PCR and Western analysis. From the phenotypic feature of the infected plants and the reduced expression abundance of DHS and eIF-5A, we concluded that NbDHS plays important roles in plant growth, development and senescence. The possible application of DHS gene in ge-netic modification of crops and horticultural plants was dis-cussed.
WANG HongzhiMA RongcaiLI RuifenWANG GuoyingWEI Jianhua
