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Damen, J.

Publications and source records attributed to Damen, J..

3 recordsLinked to original sources

Experimental and computational analyses of KEA3-dependent photosynthetic responses uncover species-specific molecular variation

- NPQ relaxation is thought to limit crop biomass and yield under natural, fluctuating light. The thylakoid K/H exchanger KEA3 accelerates NPQ relaxation by lowering the lumen proton concentration and thus should affect biomass and yield under frequent light fluctuations. - To investigate the impact of KEA3-dependent NPQ relaxation on Solanum lycopersicum (tomato), we generated knock-out and over-expression lines and measured NPQ, gas exchange, biomass and yield. We constructed a mathematical model to compare species-specific NPQ relaxation dynamics in tomato and the model plant Arabidopsis thaliana. - In polytunnel and controlled fluctuating-light conditions, KEA3-mediated NPQ relaxation did not translate into consistent differences in tomato biomass or yield. Although KEA3 levels strongly affected NPQ relaxation, more so than in A.thaliana, the resulting effects on CO2 assimilation were minor. Modeling results indicated that, besides minor changes in KEA3 regulation, the activity of PsbS, the primary NPQ trigger, largely determines the species-specific differences in NPQ relaxation. Structural models from both species predict sequence variation with impact on PsbS activation. - Manipulating KEA3 levels in tomato did not link NPQ relaxation with productivity. However, the results support robust cross-species mathematical model that accurately predicts the molecular interactions governing NPQ dynamics.

plant biology↗

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↗

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↗