title: Keeping it all together: auxin-actin crosstalk in plant development.
abstract: Polar auxin transport and the action of the actin cytoskeleton are tightly interconnected, which is documented by the finding that auxin transporters reach their final destination by active movement of secretory vesicles along F-actin tracks. Moreover, auxin transporter polarity and flexibility is thought to depend on transporter cycling that requires endocytosis and exocytosis of vesicles. In this context, we have reviewed the current literature on an involvement of the actin cytoskeleton in polar auxin transport and identify known similarities and differences in its structure, function and dynamics in comparison to non-plant organisms. By describing how auxin modulates actin expression and actin organization and how actin and its stability affects auxin-transporter endocytosis and recycling, we discuss the current knowledge on regulatory auxin-actin feedback loops. We focus on known effects of auxin and of auxin transport inhibitors on the stability and organization of actin and examine the functionality of auxin and/or auxin transport inhibitor-binding proteins with respect to their suitability to integrate auxin/auxin transport inhibitor action. Finally, we indicate current difficulties in the interpretation of organ, time and concentration-dependent auxin/auxin transport inhibitor treatments and formulate simple future experimental guidelines.
authors.affiliation: University of Fribourg, Department of Biology-Plant Biology, CH-1700 Fribourg, Switzerland.
authors.forename: Jinsheng
authors.initials: J
authors.lastname: Zhu
authors.affiliation: University of Fribourg, Department of Biology-Plant Biology, CH-1700 Fribourg, Switzerland markus.geisler@unifr.ch.
authors.forename: Markus
authors.initials: M
authors.lastname: Geisler
mesh_terms: D000199:Actins / Q000378:metabolism*; D001692:Biological Transport; D007210:Indoleacetic Acids / Q000378:metabolism*; D063245:Plant Development; D010937:Plant Growth Regulators / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D000199:Actins; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators
keywords: ABCB; Actin; PIN cycling; TWD1 ABP1.; auxin; auxin transport inhibitor