@article{LambourGlenzForneretal.2022,
  author    = {Lambour, Benjamin and Glenz, Ren{\´e} and Forner, Carmen and Krischke, Markus and Mueller, Martin J. and Fekete, Agnes and Waller, Frank},
  title     = {Sphingolipid long-chain base phosphate degradation can be a rate-limiting step in long-chain base homeostasis},
  series = {Frontiers in Plant Science},
  volume    = {13},
  journal   = {Frontiers in Plant Science},
  issn      = {1664-462X},
  doi       = {10.3389/fpls.2022.911073},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-277679},
  year      = {2022},
  abstract  = {Sphingolipid long-chain bases (LCBs) are building blocks for membrane-localized sphingolipids, and are involved in signal transduction pathways in plants. Elevated LCB levels are associated with the induction of programmed cell death and pathogen-derived toxin-induced cell death. Therefore, levels of free LCBs can determine survival of plant cells. To elucidate the contribution of metabolic pathways regulating high LCB levels, we applied the deuterium-labeled LCB D-erythro-sphinganine-d7 (D7-d18:0), the first LCB in sphingolipid biosynthesis, to Arabidopsis leaves and quantified labeled LCBs, LCB phosphates (LCB-Ps), and 14 abundant ceramide (Cer) species over time. We show that LCB D7-d18:0 is rapidly converted into the LCBs d18:0P, t18:0, and t18:0P. Deuterium-labeled ceramides were less abundant, but increased over time, with the highest levels detected for Cer(d18:0/16:0), Cer(d18:0/24:0), Cer(t18:0/16:0), and Cer(t18:0/22:0). A more than 50-fold increase of LCB-P levels after leaf incubation in LCB D7-d18:0 indicated that degradation of LCBs via LCB-Ps is important, and we hypothesized that LCB-P degradation could be a rate-limiting step to reduce high levels of LCBs. To functionally test this hypothesis, we constructed a transgenic line with dihydrosphingosine-1-phosphate lyase 1 (DPL1) under control of an inducible promotor. Higher expression of DPL1 significantly reduced elevated LCB-P and LCB levels induced by Fumonisin B1, and rendered plants more resistant against this fungal toxin. Taken together, we provide quantitative data on the contribution of major enzymatic pathways to reduce high LCB levels, which can trigger cell death. Specifically, we provide functional evidence that DPL1 can be a rate-limiting step in regulating high LCB levels.},
  language  = {en}
}
@article{SchilcherHilsmannAnkenbrandetal.2022,
  author    = {Schilcher, Felix and Hilsmann, Lioba and Ankenbrand, Markus J. and Krischke, Markus and Mueller, Martin J. and Steffan-Dewenter, Ingolf and Scheiner, Ricarda},
  title     = {Honeybees are buffered against undernourishment during larval stages},
  series = {Frontiers in Insect Science},
  volume    = {2},
  journal   = {Frontiers in Insect Science},
  issn      = {2673-8600},
  doi       = {10.3389/finsc.2022.951317},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-304646},
  year      = {2022},
  abstract  = {The negative impact of juvenile undernourishment on adult behavior has been well reported for vertebrates, but relatively little is known about invertebrates. In honeybees, nutrition has long been known to affect task performance and timing of behavioral transitions. Whether and how a dietary restriction during larval development affects the task performance of adult honeybees is largely unknown. We raised honeybees in-vitro, varying the amount of a standardized diet (150 µl, 160 µl, 180 µl in total). Emerging adults were marked and inserted into established colonies. Behavioral performance of nurse bees and foragers was investigated and physiological factors known to be involved in the regulation of social organization were quantified. Surprisingly, adult honeybees raised under different feeding regimes did not differ in any of the behaviors observed. No differences were observed in physiological parameters apart from weight. Honeybees were lighter when undernourished (150 µl), while they were heavier under the overfed treatment (180 µl) compared to the control group raised under a normal diet (160 µl). These data suggest that dietary restrictions during larval development do not affect task performance or physiology in this social insect despite producing clear effects on adult weight. We speculate that possible effects of larval undernourishment might be compensated during the early period of adult life.},
  language  = {en}
}