Upon bolting the GTR1 and GTR2 transporters mediate transport of glucosinolates to the inflorescence rather than roots.
We recently described the glucosinolate transporters GTR1 and GTR2 as actively contributing to the establishment of tissue-specific distribution of the defense compounds glucosinolates in vegetative Arabidopsis plants. Upon bolting and thereby development of the inflorescence and initiation of seed setting, the spatial distribution of glucosinolates does undergo major changes. Here we investigate the role of GTR1 and GTR2 in establishment of glucosinolate source-sink relationships in bolting plants. By in vivo feeding the exogenous p-hydroxybenzylglucosinolate to a rosette leaf or the roots of wildtype and a gtr1 gtr2 mutant, we show that this glucosinolate can specifically translocate from the rosette and the roots to the inflorescence in a GTR1- and GTR2-dependent manner. This marks that, upon bolting, the inflorescence rather than the roots constitute the strongest sink for leaf glucosinolates compared with plants in vegetative state.
DynaMo Centre of Excellence; Department of Plant and Environmental Sciences; Faculty of Science; University of Copenhagen; Frederiksberg C, Denmark.
Tonni Grube
TG
Andersen
DynaMo Centre of Excellence; Department of Plant and Environmental Sciences; Faculty of Science; University of Copenhagen; Frederiksberg C, Denmark.
Barbara Ann
BA
Halkier
D017360:Arabidopsis / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035263:Flowering Tops / Q000378:metabolism; D005961:Glucosinolates / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins / Q000235:genetics / Q000378:metabolism*; D063245:Plant Development; D018517:Plant Roots / Q000378:metabolism
D029681:Arabidopsis Proteins; C575185:GTR1 protein, Arabidopsis; C575186:GTR2 protein, Arabidopsis; D005961:Glucosinolates; D009004:Monosaccharide Transport Proteins
Arabidopsis; chemical defense distribution; feeding; glucosinolate; roots; specialized/secondary metabolites; transport