Arabidopsis YELLOW STRIPE-LIKE7 (YSL7) and YSL8 transporters mediate uptake of Pseudomonas virulence factor syringolin A into plant cells.
Syringolin A (SylA), a virulence factor secreted by certain strains of the plant pathogen Pseudomonas syringae pv. syringae, is an irreversible proteasome inhibitor imported by plant cells by an unknown transport process. Here, we report that functional expression in yeast of all 17 members of the Arabidopsis oligopeptide transporter family revealed that OLIGOPEPTIDE TRANSPORTER1 (OPT1), OPT2, YELLOW STRIPE-LIKE3 (YSL3), YSL7, and YSL8 rendered yeast cells sensitive to growth inhibition by SylA to different degrees, strongly indicating that these proteins mediated SylA uptake into yeast cells. The greatest SylA sensitivity was conferred by YSL7 and YSL8 expression. An Arabidopsis ysl7 mutant exhibited strongly reduced SylA sensitivity in a root growth inhibition assay and in leaves of ysl7 and ysl8 mutants, SylA-mediated quenching of salicylic-acid-triggered PATHOGENESIS-RELATED GENE1 transcript accumulation was greatly reduced compared with the wild type. These results suggest that YSL7 and YSL8 are major SylA uptake transporters in Arabidopsis. Expression of a YSL homolog of bean, the host of the SylA-producing P. syringae pv. syringae B728a, in yeast also conferred strong SylA sensitivity. Thus, YSL transporters, which are thought to be involved in metal homeostasis, have been hijacked by bacterial pathogens for SylA uptake into host cells.
Silvia Schelbert
SS
Hofstetter
Alexey
A
Dudnik
Heidi
H
Widmer
Robert
R
Dudler
D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism / Q000382:microbiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D015870:Gene Expression; D017930:Genes, Reporter; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009842:Oligopeptides / Q000378:metabolism; D009928:Organ Specificity; D010456:Peptides, Cyclic / Q000378:metabolism* / Q000494:pharmacology; D010802:Phylogeny; D010935:Plant Diseases / Q000382:microbiology*; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D044224:Pseudomonas syringae / Q000378:metabolism*; D011993:Recombinant Fusion Proteins; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D037521:Virulence Factors / Q000378:metabolism
D029681:Arabidopsis Proteins; D026901:Membrane Transport Proteins; D009842:Oligopeptides; D010456:Peptides, Cyclic; D011993:Recombinant Fusion Proteins; D037521:Virulence Factors; C586209:YELLOW STRIPE-LIKE7 protein, Arabidopsis; C586210:YELLOW STRIPE-LIKE8 protein, Arabidopsis; C407267:syringolin A