journal contribution
posted on 2023-05-19, 19:21 authored by Jaborsky, M, Maierhofer, T, Olbrich, A, Escalante-Perez, M, Muller, HM, Simon, J, Krol, E, Tracey Cuin, Fromm, J, Ache, P, Geiger, D, Hedrich, R Extrafloral nectaries secrete a sweet sugar cocktail that lures predator insects for protection from foraging herbivores. Apart from sugars and amino acids, the nectar contains the anions chloride and nitrate. Recent studies with Populus have identified a type of nectary covered by apical bipolar epidermal cells, reminiscent of the secretory brush border epithelium in animals. Border epithelia operate transepithelial anion transport, which is required for membrane potential and/or osmotic adjustment of the secretory cells. In search of anion transporters expressed in extrafloral nectaries, we identified PttSLAH3 (Populus tremula x Populus tremuloides SLAC1 Homologue3), an anion channel of the SLAC/SLAH family. When expressed in Xenopus oocytes, PttSLAH3 displayed the features of a voltagedependent anion channel, permeable to both nitrate and chloride. In contrast to the Arabidopsis SLAC/SLAH family members, the poplar isoform PttSLAH3 is independent of phosphorylation activation by protein kinases. To understand the basis for the autonomous activity of the poplar SLAH3, we generated and expressed chimera between kinaseindependent PttSLAH3 and kinase-dependent Arabidopsis AtSLAH3. We identified the N-terminal tail and, to a lesser extent, the C-terminal tail as responsible for PttSLAH3 kinase- (in)dependent action. This feature of PttSLAH3 may provide the secretory cell with a channel probably controlling long-term nectar secretion.History
Publication title
New PhytologistVolume
210Pagination
922-933ISSN
1469-8137Department/School
Tasmanian Institute of Agriculture (TIA)Publisher
Wiley-Blackwell Publishing Ltd.Place of publication
United KingdomRights statement
Copyright 2016 The Authors New Phytologist Copyright 2018 New Phytologist TrustSocio-economic Objectives
Management of gaseous waste from plant production (excl. greenhouse gases)
