Note: Intro -- Polar Auxin Transport -- Preface -- Contents -- Signaling in Polar Auxin Transport -- 1 Introduction -- 2 AUX1/LAXs -- 3 ABCBs -- 4 ABCB Endocytosis -- 5 Phosphorylation-Mediated Regulation of ABCB Trafficking -- 6 PINs -- 7 Modulators for the Regulation of PIN Polarity -- 7.1 ARF-GEFs and Their Modulators -- 7.2 PIN Phosphorylation -- 7.2.1 A Subset of AGC Kinases Phosphorylate the Hydrophilic Loop of PINs -- 7.2.2 Phosphorylation of the PIN Hydrophilic Loop Modulates the Subcellular Polarity of PINs -- 7.2.3 Upstream Regulatory Pathways for PIN Phosphorylation -- 7.3 Membrane Lipid Composition -- 7.4 Ubiquitylation -- 7.5 ABP1 and ROPs -- 7.6 More Regulatory Signals for Auxin Transport -- References -- Polar Auxin Transport: Cell Polarity to Patterning -- 1 Auxin: A Plant Signaling Molecule with Morphogen-Like Characters -- 1.1 Morphogenic Properties of Auxin -- 1.2 Auxin Efflux Carrier PINs -- 2 Role of PINs in Plant Development -- 2.1 Auxin and Embryogenesis -- 2.2 Auxin and Root Development -- 2.3 Auxin and Lateral Root Development -- 2.4 Auxin and Shoot Morphogenesis -- 3 PIN Trafficking and Localization -- 3.1 Action of ARF-GEF GNOM in Polar Recycling of PINs -- 3.2 Action of PID (PINOID) Kinase Providing Phosphorylation Bias for PIN Recruitment into Inverse Recycling Pathways -- 3.3 PP2A: A Protein Phosphatase Counteracting to the Action of PID Kinase -- 3.4 Role of SNX1 and VSP29 for PIN Trafficking and Localization -- 3.5 Role of Rab5 for PIN Trafficking and Localization -- 3.6 Role of ROP/RAC GTPases for PIN Trafficking and Localization -- 3.7 Importance of Sterol Composition for PIN Localization -- 4 Perspective -- References -- Signal Integration, Auxin Homeostasis, and Plant Development -- 1 Auxin Signaling -- 1.1 Auxin and Plant Development -- 1.2 Auxin Biosynthesis -- 1.3 Auxin Transport -- 1.4 Auxin Signaling. , 2 Cross talk in Plant Hormone Signaling -- 2.1 Interaction of Brassinosteroids with Auxin -- 2.2 Interaction of Ethylene with Auxin -- 2.3 Interaction of Gibberellins with Auxin -- 2.4 Interaction of Abscisic Acid with Auxin -- 2.5 Interaction of Cytokinin with Auxin -- 2.6 Interaction of Jasmonic Acid with Auxin -- 2.7 Interaction of Salicylic Acid with Auxin -- 2.8 Interaction of Strigolactones and Auxin -- 3 Conclusions -- References -- Regulation of Polar Auxin Transport by Protein Phosphorylation -- 1 Introduction -- 2 The AGC Family of Protein Kinases and Their Regulators -- 2.1 The AGC VIIIa Subfamily -- 2.2 The AGC VIIIb Subfamily -- 2.3 The NPH3/BTB Proteins as Signal Transducers of the AGC VIII Kinases -- 2.4 The AGC PDK1 Subfamily -- 3 Phosphatidylinositol Metabolism and Polar Auxin Transport -- 4 Protein Kinase CK2 -- 5 MAP Kinases -- 6 Phosphatases -- 7 Conclusions -- References -- Control of Auxin Transport by Reactive Oxygen and Nitrogen Species -- 1 Introduction -- 2 ROS Regulation of Auxin Transport -- 3 RNS Regulation of Auxin Transport -- 4 Other ROS and RNS Connections to Auxin -- 4.1 Auxin Promotes ROS Accumulation -- 4.2 ROS Represses Auxin-Inducible Promoters -- 4.3 RNS Regulation of Auxin Signaling -- 5 Conclusions -- References -- Hormonal Control of Polar Auxin Transport -- 1 Polar Auxin Transport -- 2 Subcellular Trafficking of PINs -- 3 Hormonal Control of PAT -- 3.1 Auxin-Mediated Regulation of PAT -- 3.2 Cytokinin-Mediated Regulation of PAT -- 3.3 Gibberellin-Mediated Regulation of PAT -- 3.4 Brassinosteroid-Mediated Regulation of PAT -- 3.5 Strigolactone-Mediated Regulation of PAT -- 3.6 Jasmonate-Mediated Regulation of PAT -- 3.7 ABA-Mediated Regulation of PAT -- 3.8 Ethylene-Mediated Regulation of PAT -- 4 Conclusions -- References -- Auxin Transport and Signaling in Leaf Vascular Patterning -- 1 Introduction. , 2 Induction of Vascular Strand Formation in Mature Organs -- 3 Vascular Strand Formation in Embryo Development -- 3.1 A Short History of Early Embryonic Polarity -- 3.2 From a Polar Axis to a Seedling Pattern -- 3.3 Genes in Embryo Axis Formation -- 4 Leaf Vein Patterning -- 4.1 Basic Features of Vein Patterns -- 4.2 The Origin of Vein Patterns -- 4.3 Auxin Application Inducing Vascular Strands -- 4.4 The Influence of Cellular Parameters on Vein Formation -- 4.5 The Ontogeny of Leaf Veins -- 4.6 Dynamic Routes of Auxin Flow in Leaf Primordia -- 4.7 The Flat Meristem Concept -- 5 Continuity of Vein Formation -- 6 Conclusions and Perspectives -- References -- Regulation of Polar Auxin Transport by Protein-Protein Interactions -- 1 Introduction -- 2 Posttranscriptional Regulation of Auxin Catalysts -- 3 Regulation of Auxin Catalysts by Protein-Protein Interaction -- 3.1 TWD1-ABCB Interaction -- 3.2 ABCB-PIN Interaction -- 3.3 PAT Modulators -- 4 Regulation of Auxin Transporter Activity by Protein Phosphorylation -- 4.1 PIN Phosphorylation -- 4.2 ABCB Phosphorylation -- 5 Interaction and Polarity Loops Are Interconnected -- 6 Outlook -- References -- The Role of Auxin Transport and Distribution in Plant Gravimorphogenesis -- 1 Plant Responses to Gravity -- 2 Gravitropism Mechanisms in Arabidopsis Seedlings -- 2.1 Root Gravitropism -- 2.2 Shoot Gravitropism -- 3 Gravimorphogenesis in Cucurbitaceous Plants: Gravity-Regulated Peg Formation -- 4 Possible Cellular Mechanisms Underlying the Gravity-Regulated Polarization of CsPIN1 in Cucumber Seedlings -- 5 Concluding Remarks -- References -- Polar Auxin Transport Regulation in Plant-Microbe Interactions -- 1 Introduction -- 1.1 Root-Microbe Interactions -- 1.2 Regulation of Auxin Transport in Plants -- 2 Microorganisms Alter Auxin Transport in Host Plants. , 2.1 Root Nodule Development by Rhizobia Involves Local and Long-Distance Changes in Auxin Transport -- 2.1.1 Evidence for Local Auxin Transport Inhibition by Rhizobia -- 2.1.2 Auxin Transport Regulation in Developing Nodules -- 2.1.3 Long-Distance Auxin Transport Control by Rhizobia -- 2.2 Mycorrhizal Fungi Affect the Root Auxin Balance -- 2.3 Plant-Parasitic Nematodes Alter Auxin Transport to Form Feeding Structures -- 2.4 Auxin Transport Control by Pathogenic Fungi -- 3 Conclusions and Perspectives -- References -- Auxin Biosynthesis and Polar Auxin Transport During Tropisms in Maize Coleoptiles -- 1 IAA Biosynthesis in Maize Coleoptiles -- 1.1 The Coleoptile Tip Region Is the Site of Vigorous IAA Biosynthesis -- 1.2 IAA Is Synthesized from Tryptophan -- 1.3 The IAA Biosynthetic Pathway in Maize -- 2 Basipetal Polar IAA Transport and Lateral IAA Transport During Tropic Responses in Maize Coleoptiles -- 2.1 Basipetal Polar IAA Transport in Maize Coleoptiles -- 2.2 Gravitropism and Phototropism in the Coleoptiles -- 2.3 Lateral IAA Transport and Asymmetric IAA Distribution During Tropic Responses -- 2.4 Candidate Genes Involved in Tropic Responses in Monocot Coleoptiles -- 3 Conclusions -- References -- Signaling and Transport of Auxin and Plant Development -- 1 Introduction -- 2 Root Tropic Responses -- 3 Transport Inhibitor Response1/Arabidopsis F-Box Proteins (AFBs) and Membrane Sterol Regulation of Auxin Transport -- 4 Auxin Binding Protein1 and Clathrin-Dependent Regulation of Auxin Transport -- 5 Vacuolar Targeting of PIN Proteins by Light Signaling -- 6 Auxin Transport Regulation of Legume-Rhizobia Symbiotic Interactions -- 7 Auxin Transport Regulation of Compound Leaf Development -- 8 Auxin Efflux PIN Proteins in M. truncatula -- 9 Concluding Remarks -- References -- From Auxin Transport to Patterning. , 1 Introduction: Auxin as a Crucial Morphogenetic Regulator in Plant -- 2 Auxin Transport as a Pattern-Generating Process -- 2.1 The Basic Cellular Machinery -- 2.1.1 Auxin Efflux Carriers -- 2.1.2 Auxin Influx Carriers and Other Regulators of Polar Auxin Transport -- 2.2 From Transport to Pattern: A Key Role for Modeling -- 2.2.1 Auxin Distributions in Different Organs -- 2.2.2 Different Feedback Models for Auxin Transport -- The Canalization Hypothesis: Transporting Auxin with the Flux -- Transport Against the Gradient -- Combined Model -- 2.2.3 Towards a Mechanistic View of Patterned Auxin Transport -- Cell-Cell Communication via the ROP Pathway -- A Role for Biomechanics? -- Mechanistic Insights: Conclusions -- 3 From Auxin Distribution to Downstream Gene Expression Patterns -- 4 Conclusions and Perspectives -- References -- Plant Competition: Light Signals Control Polar Auxin Transport -- 1 History -- 2 Phototropism -- 3 Shade Avoidance -- 4 Conclusions and Future Perspectives -- References -- Auxin and Temperature Stress: Molecular and Cellular Perspectives -- 1 Introduction -- 2 Auxin -- 2.1 Auxin Synthesis -- 2.2 Auxin Transport -- 2.3 Auxin Gradient -- 3 Temperature Stress -- 3.1 Cold Temperature -- 3.2 High Temperature -- 4 Auxin and Temperature Stress -- 4.1 Low Temperature and Auxin -- 4.2 Auxin and High Temperature -- 5 Concluding Remarks -- References -- A Fertile Field: The Mutual Influence and Parallel Histories of Auxin and Flavonoids -- 1 Introduction -- 2 Evolutionary Origins -- 3 Auxin Synthesis and Function -- 4 Flavonoids: Synthesis and Distribution -- 4.1 Function and Visualisation of Flavonoids -- 4.2 How Are Flavonoids Observed in Plant Tissues? -- 4.3 Flavonoids and Auxin Regulatory Functions -- 4.4 Flavonoid Regulation of Auxin Gradients: Growth. , 4.5 Which Proteins and Flavonoids Are Responsible for Regulation, and in Which Direction?.