title: Strigolactone analog GR24 triggers changes in PIN2 polarity, vesicle trafficking and actin filament architecture.
abstract: Strigolactones (SLs) are plant hormones that regulate shoot and root development in a MAX2-dependent manner. The mechanism underlying SLs' effects on roots is unclear. We used root hair elongation to measure root response to SLs. We examined the effects of GR24 (a synthetic, biologically active SL analog) on localization of the auxin efflux transporter PIN2, endosomal trafficking, and F-actin architecture and dynamics in the plasma membrane (PM) of epidermal cells of the primary root elongation zone in wildtype (WT) Arabidopsis and the SL-insensitive mutant max2. We also recorded the response to GR24 of trafficking (tir3), actin (der1) and PIN2 (eir1) mutants. GR24 increased polar localization of PIN2 in the PM of epidermal cells and accumulation of PIN2-containing brefeldin A (BFA) bodies, increased ARA7-labeled endosomal trafficking, reduced F-actin bundling and enhanced actin dynamics, all in a MAX2-dependent manner. Most of the der1 and tir3 mutant lines also displayed reduced sensitivity to GR24 with respect to root hair elongation. We suggest that SLs increase PIN2 polar localization, PIN2 endocytosis, endosomal trafficking, actin debundling and actin dynamics in a MAX2-dependent fashion. This enhancement might underlie the WT root's response to SLs, and suggests noncell autonomous activity of SLs in roots.
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Nirali
authors.initials: N
authors.lastname: Pandya-Kumar
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.|The Robert H. Smith Faculty of Agriculture Food and Environment, The Hebrew University of Jerusalem, Rehovot, 76100, Israel.
authors.forename: Rony
authors.initials: R
authors.lastname: Shema
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Manoj
authors.initials: M
authors.lastname: Kumar
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Einav
authors.initials: E
authors.lastname: Mayzlish-Gati
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Danny
authors.initials: D
authors.lastname: Levy
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Hanita
authors.initials: H
authors.lastname: Zemach
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Eduard
authors.initials: E
authors.lastname: Belausov
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Smadar
authors.initials: S
authors.lastname: Wininger
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Abu-Abied
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Yoram
authors.initials: Y
authors.lastname: Kapulnik
authors.affiliation: Institute of Plant Sciences, Agricultural Research Organization (ARO), the Volcani Center, Bet Dagan, 50250, Israel.
authors.forename: Hinanit
authors.initials: H
authors.lastname: Koltai
mesh_terms: D008841:Actin Cytoskeleton / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000166:cytology / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D004705:Endocytosis; D011992:Endosomes / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D006575:Heterocyclic Compounds, 3-Ring / Q000494:pharmacology*; D007783:Lactones / Q000494:pharmacology*; D009154:Mutation; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins
chemical_list: D029681:Arabidopsis Proteins; D006575:Heterocyclic Compounds, 3-Ring; D007783:Lactones; D011993:Recombinant Fusion Proteins; C000591191:GR24 strigolactone; C117013:AT5G57090 protein, Arabidopsis
keywords: PIN2; actin; endocytosis; endosomal trafficking; max2; plasma membrane; root; strigolactone