Biology subjects

Persson, D. P.

Publications and source records attributed to Persson, D. P..

2 recordsLinked to original sources

bioRxiv2024

Specific redox and iron homeostasis responses in the root tip of Arabidopsis upon zinc excess

O_LIZinc (Zn) excess negatively impacts primary root growth in Arabidopsis. Yet, the effects of Zn excess on specific growth processes in the root tip remain largely unexplored. C_LIO_LITranscriptomics, ionomics and metabolomics were used to examine the specific impact of Zn excess on the root tip (RT) compared to the remaining root (RR). C_LIO_LIZn excess exposure resulted in shortened root apical meristem and elongation zone, with differentiation initiating closer to the tip of the root. Zn accumulated at a lower concentration in the RT than in RR. This pattern was associated with lower expression of Zn homeostasis and Fe deficiency response genes. C_LIO_LIA distinct distribution of Zn and Fe in RT and RR was highlighted by Laser Ablation ICP-MS analysis. C_LIO_LISpecialized Trp-derived metabolism genes, typically associated with redox and biotic stress responses, were specifically up-regulated in the RT upon Zn excess, among those Phytoalexin Deficient 3 (PAD3) encoding the last enzyme of camalexin synthesis. In roots of wild-type seedlings, camalexin concentration increased by 6-fold upon Zn excess and a pad3 mutant displayed increased Zn sensitivity and an altered ionome. C_LIO_LIOur results indicate that distinct redox and iron homeostasis mechanisms are key elements of the response to Zn excess in the RT. C_LI

plant biology↗

bioRxiv2022

Endodermal suberin deposition restricts potassium leakage from roots

O_LIThe endodermis is a checkpoint for ions and water escaping or entering the root. It has been hypothesized that suberin acts as a physical barrier preventing potassium (K) leakage from the stele during translocation, but attempts to support this idea has yielded contradictory results. C_LIO_LIWe developed a Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) based element bioimaging method to study K leakage from roots with different suberin deposition, where we show that cesium (Cs) is an excellent tracer for K. C_LIO_LIElement bioimaging of roots and total shoot concentrations from various Arabidopsis thaliana mutants all showed a positive relationship between suberin deposition and K translocation efficiency. In addition, images from the fully suberized barley (Hordeum vulgare) seminal roots revealed a strongly reduced K leakage compared to less suberized root zones. C_LIO_LINodal roots form a scattered deposition of suberin towards the phloem in the mature root zone. This incomplete suberin deposition also restrict K leakage efficiently. C_LIO_LICollectively, our findings provide experimental evidence that suberin act as a barrier for K leakage upon root-to-shoot translocation by restricting K movement over the endodermis from the stele to cortex. C_LI

plant biology↗