@article{AlbersUestuenWitzeletal.2019,
  author    = {Albers, Philip and {\"U}st{\"u}n, Suayib and Witzel, Katja and Kraner, Max Erdmund and B{\"o}rnke, Frederik},
  title     = {A Remorin from Nicotiana benthamiana Interacts with the Pseudomonas Type-III Effector Protein HopZ1a and is Phosphorylated by the Immune-Related Kinase PBS1},
  series = {Molecular Plant-Microbe Interactions},
  volume    = {32},
  journal   = {Molecular Plant-Microbe Interactions},
  number    = {9},
  publisher = {Amer phytopathological SOC},
  address   = {ST Paul},
  issn      = {0894-0282},
  doi       = {10.1094/MPMI-04-19-0105-R},
  pages     = {1229 -- 1242},
  year      = {2019},
  abstract  = {The plasma membrane (PM) is at the interface of plant-pathogen interactions and, thus, many bacterial type-III effector (T3E) proteins target membrane-associated processes to interfere with immunity. The Pseudomonas syringae T3E HopZ1a is a host cell PM-localized effector protein that has several immunity-associated host targets but also activates effector-triggered immunity in resistant backgrounds. Although HopZ1a has been shown to interfere with early defense signaling at the PM, no dedicated PM-associated HopZ1a target protein has been identified until now. Here, we show that HopZ1a interacts with the PM-associated remorin protein NbREM4 from Nicotiana benthamiana in several independent assays. NbREM4 relocalizes to membrane nanodomains after treatment with the bacterial elicitor flg22 and transient overexpression of NbREM4 in N. benthamiana induces the expression of a subset of defense-related genes. We can further show that NbREM4 interacts with the immune-related receptor-like cytoplasmic kinase avrPphB-susceptible 1 (PBS1) and is phosphorylated by PBS1 on several residues in vitro. Thus, we conclude that NbREM4 is associated with early defense signaling at the PM. The possible relevance of the HopZ1a-NbREM4 interaction for HopZ1a virulence and avirulence functions is discussed.},
  language  = {en}
}
@article{WitzelAbuRishaAlbersetal.2019,
  author    = {Witzel, Katja and Abu Risha, Marua and Albers, Philip and B{\"o}rnke, Frederik and Hanschen, Franziska S.},
  title     = {Identification and Characterization of Three Epithiospecifier Protein Isoforms in Brassica oleracea},
  series = {Frontiers in plant science},
  volume    = {10},
  journal   = {Frontiers in plant science},
  publisher = {Frontiers Research Foundation},
  address   = {Lausanne},
  issn      = {1664-462X},
  doi       = {10.3389/fpls.2019.01552},
  pages     = {14},
  year      = {2019},
  abstract  = {Glucosinolates present in Brassicaceae play a major role in herbivory defense. Upon tissue disruption, glucosinolates come into contact with myrosinase, which initiates their breakdown to biologically active compounds. Among these, the formation of epithionitriles is triggered by the presence of epithiospecifier protein (ESP) and a terminal double bond in the glucosinolate side chain. One ESP gene is characterized in the model plant Arabidopsis thaliana (AtESP; At1g54040.2). However, Brassica species underwent genome triplication since their divergence from the Arabidopsis lineage. This indicates the presence of multiple ESP isoforms in Brassica crops that are currently poorly characterized. We identified three B. oleracea ESPs, specifically BoESP1 (LOC106296341), BoESP2 (LOC106306810), and BoESP3 (LOC106325105) based on in silico genome analysis. Transcript and protein abundance were assessed in shoots and roots of four B. oleracea vegetables, namely broccoli, kohlrabi, white, and red cabbage, because these genotypes showed a differential pattern for the formation of glucosinolate hydrolysis products as well for their ESP activity. BoESP1 and BoESP2 were expressed mainly in shoots, while BoESP3 was abundant in roots. Biochemical characterization of heterologous expressed BoESP isoforms revealed different substrate specificities towards seven glucosinolates: all isoforms showed epithiospecifier activity on alkenyl glucosinolates, but not on non-alkenyl glucosinolates. The pH-value differently affected BoESP activity: while BoESP1 and BoESP2 activities were optimal at pH 6-7, BoESP3 activity remained relatively stable from pH 4 to 7. In order test their potential for the in vivo modification of glucosinolate breakdown, the three isoforms were expressed in A. thaliana Hi-0, which lacks AtESP expression, and analyzed for the effect on their respective hydrolysis products. The BoESPs altered the hydrolysis of allyl glucosinolate in the A. thaliana transformants to release 1-cyano-2,3-epithiopropane and reduced formation of the corresponding 3-butenenitrile and allyl isothiocyanate. Plants expressing BoESP2 showed the highest percentage of released epithionitriles. Given these results, we propose a model for isoform-specific roles of B. oleracea ESPs in glucosinolate breakdown.},
  language  = {en}
}
@article{WitzelAbuRishaAlbersetal.2020,
  author    = {Witzel, Katja and Abu Risha, Marua and Albers, Philip and B{\"o}rnke, Frederik and Hanschen, Franziska S.},
  title     = {Corrigendum : Identification and characterization of three epithiospecifier protein isoforms in Brassica oleracea / Witzel, Katja; Abu Risha, Marua; Albers, Philip; B{\"o}rnke, Frederike; Hanschen, Franziska S. - Lausanne: Frontiers Media, 2019. - Frontiers in plant science : FPLS. - 10 (2019) art. 1552. - doi: 10.3389/fpls.2019.01552},
  series = {Frontiers in plant science : FPLS},
  volume    = {11},
  journal   = {Frontiers in plant science : FPLS},
  publisher = {Frontiers Media},
  address   = {Lausanne},
  issn      = {1664-462X},
  doi       = {10.3389/fpls.2020.00523},
  pages     = {2},
  year      = {2020},
  language  = {en}
}