title: PIN proteins perform a rate-limiting function in cellular auxin efflux.
abstract: Intercellular flow of the phytohormone auxin underpins multiple developmental processes in plants. Plant-specific pin-formed (PIN) proteins and several phosphoglycoprotein (PGP) transporters are crucial factors in auxin transport-related development, yet the molecular function of PINs remains unknown. Here, we show that PINs mediate auxin efflux from mammalian and yeast cells without needing additional plant-specific factors. Conditional gain-of-function alleles and quantitative measurements of auxin accumulation in Arabidopsis and tobacco cultured cells revealed that the action of PINs in auxin efflux is distinct from PGP, rate-limiting, specific to auxins, and sensitive to auxin transport inhibitors. This suggests a direct involvement of PINs in catalyzing cellular auxin efflux.
authors.affiliation: Institute of Experimental Botany, the Academy of Sciences of the Czech Republic, 165 02 Prague 6, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Petrásek
authors.forename: Jozef
authors.initials: J
authors.lastname: Mravec
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Bouchard
authors.forename: Joshua J
authors.initials: JJ
authors.lastname: Blakeslee
authors.forename: Melinda
authors.initials: M
authors.lastname: Abas
authors.forename: Daniela
authors.initials: D
authors.lastname: Seifertová
authors.forename: Justyna
authors.initials: J
authors.lastname: Wisniewska
authors.forename: Zerihun
authors.initials: Z
authors.lastname: Tadele
authors.forename: Martin
authors.initials: M
authors.lastname: Kubes
authors.forename: Milada
authors.initials: M
authors.lastname: Covanová
authors.forename: Pankaj
authors.initials: P
authors.lastname: Dhonukshe
authors.forename: Petr
authors.initials: P
authors.lastname: Skupa
authors.forename: Eva
authors.initials: E
authors.lastname: Benková
authors.forename: Lucie
authors.initials: L
authors.lastname: Perry
authors.forename: Pavel
authors.initials: P
authors.lastname: Krecek
authors.forename: Ok Ran
authors.initials: OR
authors.lastname: Lee
authors.forename: Gerald R
authors.initials: GR
authors.lastname: Fink
authors.forename: Markus
authors.initials: M
authors.lastname: Geisler
authors.forename: Angus S
authors.initials: AS
authors.lastname: Murphy
authors.forename: Christian
authors.initials: C
authors.lastname: Luschnig
authors.forename: Eva
authors.initials: E
authors.lastname: Zazímalová
authors.forename: Jirí
authors.initials: J
authors.lastname: Friml
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000254:growth & development / Q000378:metabolism* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D018522:Gravitropism; D006367:HeLa Cells; D006801:Humans; D007210:Indoleacetic Acids / Q000378:metabolism*; D007700:Kinetics; D026901:Membrane Transport Proteins / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D009280:Naphthaleneacetic Acids / Q000378:metabolism; D010797:Phthalimides / Q000494:pharmacology; D018517:Plant Roots / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics; D014026:Nicotiana; D014162:Transfection; D014170:Transformation, Genetic
chemical_list: D018528:ATP-Binding Cassette Transporters; D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D026901:Membrane Transport Proteins; D009280:Naphthaleneacetic Acids; D010797:Phthalimides; C114215:ATPGP1 protein, Arabidopsis; C116363:PIN1 protein, Arabidopsis; C117013:AT5G57090 protein, Arabidopsis; C451260:PIN4 protein, Arabidopsis; C479554:PIN7 protein, Arabidopsis; C002687:alpha-naphthylphthalamic acid; C034182:1-naphthaleneacetic acid