Biology subjects

Kloth, K. J.

Publications and source records attributed to Kloth, K. J..

3 recordsLinked to original sources

bioRxiv2026

Pseudomonas volatiles shape the root transcriptome and microbiome to promote plant growth under drought

O_LIVolatile organic compounds (VOCs) emitted by soil bacteria influence interactions with other soil microbes and with plant roots. While their potential as plant-growth promoters is well recognized, their role in promoting plant resilience to abiotic stress and the underlying molecular mechanisms remains poorly understood. Here, we investigate the role of Pseudomonas VOCs in enhancing plant resilience to drought stress. C_LIO_LIArabidopsis thaliana plants were exposed to VOCs emitted by Pseudomonas strains under both control and osmotic-stress conditions. VOC exposure generally enhanced plant growth, and this effect was even more pronounced under both drought and salt stress. Transcriptomic analysis revealed that VOC exposure modulates key stress-responsive pathways, including those related to abscisic acid biosynthesis and signalling, sugar transport, iron uptake, aliphatic glucosinolate biosynthesis, and plant defences. Using Arabidopsis mutants, we identified abscisic acid and aliphatic glucosinolates as important components in mediating the plant response to VOCs. SWEET11/12 sugar transporters and ABA signaling genes were downregulated by VOCs exposure, in order to allow for a positive regulation of lateral root numbers (in case of SWEET genes) and plant growth in general under drought stress. In summary, using metabolomics, transcriptomics and functional analysis, we showed a negative cross-talk between the effects of VOCs on plant growth and glucosinolate production, whereas a positive interaction was observed between the biosynthesis of coumarins and VOCs. C_LIO_LINotably, VOCs also improved drought tolerance in soil-grown Brassica oleracea plants. We showed that VOC treatment altered the root-associated microbiome under drought, leading to a community composition more similar to that of well-watered plants. C_LIO_LIOur results show that Pseudomonas emitted VOCs can promote plant growth under drought conditions, linked to root transcriptional reprogramming and direct or indirect microbiome modulation. C_LI

plant biology↗

bioRxiv2025

Stationary phloem proteins and their effects on viruses, aphids, and cyst nematodes in Arabidopsis

The phloem is a specialized tissue that facilitates systemic transport of carbohydrates and signal molecules, making it a common target for viruses, phloem-feeding insects, and cyst nematodes. In Arabidopsis, the stationary phloem-associated SIEVE ELEMENT-LINING CHAPERONE1 (SLI1) and RESTRICTED TEV MOVEMENT (RTM) proteins restrict insect phloem-feeding and potyviruses systemic transport, respectively. However, their broader roles in plant-attacker interactions remain largely unexplored. We investigated the roles of SLI1, RTM1, RTM2, and RTM3 in tobacco etch virus (TEV) infection, as well as in Myzus persicae and Heterodera schachtii infestations using Arabidopsis mutants. Systemic TEV movement was quantified, aphid behaviour and reproduction were assessed, and cyst nematode infection was monitored. SLI1 did not restrict TEV systemic movement, RTM3 reduced M. persicae reproduction without altering feeding behaviour, SLI1, RTM2, and RTM3 supported H. schachtii infection and feeding site expansion, and confocal images indicated a possible role of the proteins in de novo synthesis of sieve tubes around syncytia. These findings reveal that stationary phloem proteins exert dual and target-specific effects, limiting some attackers while inadvertently facilitating others. This highlights the complexity of phloem-based immunity and underscores the need to unravel its underlying mechanisms to develop strategies to reduce multiple pest and pathogen burdens simultaneously. HighlightStationary phloem proteins SLI1, RTM1, RTM2, and RTM3 exert dual and target-specific effects against tobacco etch virus, Myzus persicae, and Heterodera schachtii.

plant biology↗

bioRxiv2022

Arabidopsis latent virus 1, a comovirus widely spread in Arabidopsis thaliana collections

O_LITranscriptome studies of Illumina RNA-seq datasets of different Arabidopsis thaliana natural accessions and T-DNA mutants revealed the presence of two virus-like RNA sequences which showed the typical two segmented genome characteristics of a comovirus. C_LIO_LIThis comovirus did not induce any visible symptoms in infected Arabidopsis plants cultivated under standard laboratory conditions. Hence it was named Arabidopsis latent virus 1 (ArLV1). Virus infectivity in Arabidopsis plants was confirmed by RT-qPCR, transmission electron microscopy and mechanical inoculation. ArLV1 can also mechanically infect Nicotiana benthamiana, causing distinct mosaic symptoms. C_LIO_LIA bioinformatics investigation of Arabidopsis RNA-Seq repositories, including nearly 6500 Sequence Read Archives (SRAs) in the NCBI SRA database, revealed the presence of ArLV1 in 25% of all archived natural Arabidopsis accessions and in 8.5% of all analyzed SRAs. ArLV1 could also be detected in Arabidopsis plants collected from the wild. C_LIO_LIArLV1 is highly seed-transmissible with up to 40% incidence on the progeny derived from infected Arabidopsis plants. This has likely led to a worldwide distribution in the model plant Arabidopsis with yet unknown effects on plant performance in a substantial number of studies. C_LI Plain language summaryWe identified Arabidopsis latent virus 1 (ArLV1), a comovirus that infects the model plant Arabidopsis thaliana without causing any visible symptoms. It is efficiently spread by transmission via seeds to the plant progeny. ArLV1 is infectious to Arabidopsis plants and another model plant, Nicotiana benthamiana. By analyzing public sequencing data, we found that ArLV1 is widely spread in Arabidopsis laboratory collections worldwide. Moreover, it was also detected in wild Arabidopsis plants collected from different locations in the Netherlands and Spain, suggesting that it is a virus that naturally occurs in Arabidopsis.

plant biology↗