title: Allyl Isothiocyanate Inhibits Actin-Dependent Intracellular Transport in Arabidopsis thaliana.
abstract: Volatile allyl isothiocyanate (AITC) derives from the biodegradation of the glucosinolate sinigrin and has been associated with growth inhibition in several plants, including the model plant Arabidopsis thaliana. However, the underlying cellular mechanisms of this feature remain scarcely investigated in plants. In this study, we present evidence of an AITC-induced inhibition of actin-dependent intracellular transport in A. thaliana. A transgenic line of A. thaliana expressing yellow fluorescent protein (YFP)-tagged actin filaments was used to show attenuation of actin filament movement by AITC. This appeared gradually in a time- and dose-dependent manner and resulted in actin filaments appearing close to static. Further, we employed four transgenic lines with YFP-fusion proteins labeling the Golgi apparatus, endoplasmic reticulum (ER), vacuoles and peroxisomes to demonstrate an AITC-induced inhibition of actin-dependent intracellular transport of or, in these structures, consistent with the decline in actin filament movement. Furthermore, the morphologies of actin filaments, ER and vacuoles appeared aberrant following AITC-exposure. However, AITC-treated seedlings of all transgenic lines tested displayed morphologies and intracellular movements similar to that of the corresponding untreated and control-treated plants, following overnight incubation in an AITC-absent environment, indicating that AITC-induced decline in actin-related movements is a reversible process. These findings provide novel insights into the cellular events in plant cells following exposure to AITC, which may further expose clues to the physiological significance of the glucosinolate-myrosinase system.
authors.affiliation: Department of Biology, the Norwegian University of Science and Technology, Høgskoleringen 5, N-7491 Trondheim, Norway. bjornar.sporsheim@ntnu.no.
authors.forename: Bjørnar
authors.initials: B
authors.lastname: Sporsheim
authors.affiliation: Department of Biology, the Norwegian University of Science and Technology, Høgskoleringen 5, N-7491 Trondheim, Norway. anders.overby@ntnu.no.
authors.forename: Anders
authors.initials: A
authors.lastname: Øverby
authors.affiliation: Department of Biology, the Norwegian University of Science and Technology, Høgskoleringen 5, N-7491 Trondheim, Norway. atle.m.bones@ntnu.no.
authors.forename: Atle Magnar
authors.initials: AM
authors.lastname: Bones
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D000199:Actins / Q000378:metabolism* / Q000648:ultrastructure; D017360:Arabidopsis / Q000166:cytology / Q000378:metabolism*; D001692:Biological Transport; D017879:Isothiocyanates / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D000199:Actins; D017879:Isothiocyanates; D010940:Plant Proteins; C004471:allyl isothiocyanate
keywords: actin cytoskeleton; allyl isothiocyanate; glucosinolate; intracellular transport; plant defense mechanism; sinigrin