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Gorzolka, K.

Publications and source records attributed to Gorzolka, K..

3 recordsLinked to original sources

Lethal effects of the wild potato Solanum bulbocastanum on the planthopper Pentastiridius leporinus, a vector of bacterial pathogens in potato

The planthopper Pentastiridius leporinus [Hemiptera: Cixiidae] is a vector of the two plant pathogenic bacteria Candidatus Arsenophonus phytopathogenicus and Candidatus Phytoplasma solani in potato. An infection leads to symptoms such as rubbery and non-processable tubers and consequently to substantial decreases in yield and tuber quality as well as to abandonment of seed potato production in affected areas. Up to date, resistant potato varieties are not yet known, and the tool box of integrated pest management to prevent the spread of P. leporinus as causal vector is quite limited. Mortality experiments designed as no-choice trials on potato cultivar Gala (Solanum tuberosum) and on its wild relative S. bulbocastanum revealed significant effects of the latter on the survival rate of the vector. LC/MS analysis of the insects and their intestines showed that acyl solamines were retrieved only in individuals from the S. bulbocastanum plants. Furthermore, choice-tests were carried out to study the vector behavior. A preference towards S. bulbocastanum vs. S. tuberosum Gala was observed despite its lethal effects. Volatile organic compounds of the two different species were collected and analyzed by GC/MS. The two profiles differed in 39 of 80 compounds. The wild potato species S. bulbocastanum and its compounds are discussed as potential starting points for further research on sustainable management of P. leporinus. Key MessageO_LIWe tested a wild potato against a planthopper which vectors pathogenic bacteria to potato C_LIO_LIWild potato led to higher mortality of the planthopper but was preferred against cultivated potato C_LIO_LIUptake assays suggest that the phloem sucking planthopper is taking up xylem sap as well C_LIO_LIAcyl solamines were only found in guts from planthoppers sucking on the wild potato C_LIO_LIOur results present a starting point for new approaches for sustainable vector control C_LI

ecology↗

The plant specific cohesin subunit SYN4 contributes to 3D genome organization and activity

O_LIChromatin architecture in the cells of animals and fungi influences gene expression. The molecular factors that influence higher genome architecture in plants and their effects on gene expression remain unknown. Cohesin complexes, conserved in eukaryotes, are essential factors in genome structuring. Here, we investigated the relevance of the plant-specific somatic cohesin subunit SYN4 for chromatin organisation in Arabidopsis thaliana. C_LIO_LIPlants mutated in SYN4 were studied using HRM, Hi-C, RNA sequencing, untargeted and targeted metabolomics and physiological assays to understand the role of this plant-specific cohesin. C_LIO_LIWe show that syn4 mutants exhibit altered intra- and interchromosomal interactions, expressed as sharply reduced contacts between telomeres and chromosome arms but not between centromeres, and differences in the placement and number of topologically associated domains (TADs)-like structures. By transcriptome sequencing, we also show that syn4 mutants have altered gene expression, including numerous genes that control abiotic stress responses. C_LIO_LIThe response to drought stress in Arabidopsis is strongly influenced by the genome structure in syn4 mutants, potentially due to altered expression of CYP707A3, an ABA 8-hydroxylase. C_LI In briefThe 3D architecture of the genome extensively influences gene expression in animals and fungi. We show that the plant-specific cohesin subunit SYN4 affects intra- and interchromosomal interactions including telomere clustering, with consequences for the expression of genes of transient and induced biological pathways and the biosynthesis of bioactive compounds. Highly condensed genome structures at the CYP707A3 locus positively affects the stress response to water deprivation regulated by abscisic acid.

genetics↗

A phospho-switch provided by LRR receptor-like kinase, ALK1/QSK1/KIN7, prioritizes ABCG36/PEN3/PDR8 transport toward defense

Based on its proposed substrate preferences, the ABC transporter, ABCG36/PDR8/PEN3, from the model plant Arabidopsis stands at the cross-road between growth and defence. Recently, ABCG36 was shown to export a few indolic compounds, including the auxin precursor, indole-3-butyric acid (IBA), and to be implicated in the export of the major phytoalexin of Arabidopsis, camalexin, although clear-cut proof of camalexin transport activity is still lacking. Here we provide strong evidence that ABCG36 catalyses the direct, ATP-dependent export of camalexin over the plasma membrane, however, most likely in functional interplay with non-camalexin transporting ABCG isoforms. We identify the leucin-rich repeat receptor-like kinase, Auxin-induced LRR Kinase1 (ALK1/KIN7/QSK1), as a functional kinase to physically interact with and phosphorylate ABCG36. ABCG36 phosphorylation by ALK1 represses unilaterally IBA but not camalexin export leading to a prioritization of ABCG transport toward defense. As a consequence, phospho-dead mutants of ABCG36, like alk1 and abcg36 alleles, are hypersensitive toward infection with the root pathogen, F. oxysporum, caused by elevated fungal progression. Our findings indicate a novel, direct regulatory circuit between a receptor kinase and an ABC transporter determining transporter substrate specificity. It appears that growth and defense balance decisions in plants are performed on the transporter level by means of a reversible phospho-switch.

plant biology↗