Yttrium oxide nanoparticles (nY 2 O 3 ), one of the broadly used rare earth nanoparticles, can interact with plants and possibly cause plant health and environmental impacts, but the plant defense response particularly at the nanoparticle−cell interface is largely unknown. To elucidate this, Bright Yellow 2 (BY-2) tobacco (Nicotiana tabacum L.) suspension-cultured cells were exposed to 50 mg L −1 nY 2 O 3 (30 nm) for 12 h. Although 42.2% of the nY 2 O 3 remained outside of protoplasts, nY 2 O 3 could still traverse the cell wall and was partially deposited inside the vacuole. In addition to growth inhibition, morphological and compositional changes in cell walls occurred. Together with a locally thickened (7−13-fold) cell wall, increased content (up to 58%) of pectin and reduction in (up to 29%) hemicellulose were observed. Transcriptome analysis revealed that genes involved in cell wall metabolism and remodeling were highly regulated in response to nY 2 O 3 stress. Expression of genes for pectin synthesis and degradation was up-and down-regulated by 31−78% and 13−42%, respectively, and genes for xyloglucan and pectin modifications were up-and down-regulated by 82% and 81− 92%, respectively. Interestingly, vesicle trafficking seemed to be activated, enabling the repair and defense against nY 2 O 3 disturbance. Our findings indicate that, although nY 2 O 3 generated toxicity on BY-2 cells, it is very likely that during the recovery process cell wall remodeling was initiated to gain resistance to nY 2 O 3 stress, demonstrating the plant's cellular regulatory machinery regarding repair and adaptation to nanoparticles like nY 2 O 3 .

In this study, Bright Yellow 2 (BY-2) tobacco (Nicotiana tabacum L.) cell suspensions exposed to manganese ferrite nanoparticles (nMnFe2O4) or nitrogen-doped carbon dots (N-CDs) were analyzed for hormonal pathways. The...

Nanomaterials can induce plant tolerance to abiotic environmental stresses, whereas the sensing mechanism and the resulting response at cellular level need further exploration. Bright Yellow 2 tobacco (Nicotiana tabacum L.)...