Membrane Transport in Plants Annual Plant Reviews, Volume Fifteen

Michael R. Blatt

• Publisher: Blackwell
• Year: 2026
• Topic: Biological Sciences
• eBook ISBN:
  9781040894354
• Subtopic: Botany
• Index: Biological Sciences

Research in to membrane transport has advanced rapidly in recent years, following the availability of new biophysical techniques, the integration of structural and molecular approaches, and developments in molecular genomics. With an expanding population, agricultural production is pushed increasingly into marginal areas, promoting interest in the genetic engineering of crop species to cope with these conditions. Membrane Transport in Plants provides on overview of our current understanding of plant membrane transport in the light of recent developments. The volume is directed at researchers and professionals in plant cell biology, biochemistry and physiology.

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• 1 Concepts and techniques in plant membrane physiology
• 1.1 Introduction
• 1.2 Plant membrane transport
• 1.3 Intracellular recording and the voltage clamp
• 1.4 Patch clamp
• 1.5 Separating and analysing membrane currents
• 1.5.1 Steady-state current
• 1.5.2 Current relaxations and ion channel gating
• 1.5.3 Analysing single-channel current
• 1.6 Microinjection and perfusion
• 1.7 Radiotracer flux analysis
• 1.8 Conclusion
• Acknowledgements
• References
• 2 Electrophysiology equipment and software
• 2.1 Introduction
• 2.2 Voltage clamp protocols
• 2.2.1 Voltage stepping protocols
• 2.2.2 Voltage ramp protocols
• 2.2.3 ‘Tail current’ protocols
• 2.2.4 Time-variant protocols
• 2.2.5 Extended single-channel recording
• 2.3 Equipment and hardware
• 2.3.1 The working environment
• 2.3.2 Capillaries and micropipettes
• 2.3.3 Electronics
• 2.3.4 Data acquisition and control boards
• 2.3.4.1 Scientific Solutions’ LabMaster® Boards
• 2.3.4.2 Instrutech Corporation’s ITC Interfacee
• 2.3.4.3 Axon Instruments’ DigiData Systems
• 2.3.4.4 National Instruments’ Cards
• 2.3.4.5 Data Translation
• 2.3.5 Choosing a computer
• 2.4 Computer software
• 2.4.1 Basic requirements
• 2.4.2 Signal conditioning
• 2.4.3 Data analysis tools
• 2.4.3.1 IV analysis
• 2.4.3.2 Curve fitting
• 2.4.3.3 Single-channel analysis
• 2.4.3.4 Data export
• 2.4.4 Commercially available software
• 2.4.4.1 Pulse+PulseFit (HEKA Elektronik GmbH)
• 2.4.4.2 The pClamp Suite (Axon Instruments)
• 2.4.4.3 Other commercial packages
• 2.4.4.4 Whole Cell Patch
• 2.5 Henry II’s EP Suite
• 2.5.1 Overview
• 2.5.2 The Henry II application
• 2.5.2.1 The protocol editor
• 2.5.2.2 Run-time monitoring and analysis
• 2.5.2.3 Post-acquisition data analysis
• 2.5.3 The Vicar V2 virtual chart recorder
• 2.5.4 Noise reduction and removal with N-Pro V2
• 2.5.5 The Pandora’ application
• 2.5.6 The Y-Science ADC/DAC board drivers
• References
• 3 Structure, function and regulation of primary H+ and Ca2+ pumps
• 3.1 Pumps in plants
• 3.2 Proton pumps in plant cells
• 3.2.1 Plasma membrane H+ -ATPase
• 3.2.1.1 Physiological role
• 3.2.1.2 Genetics
• 3.2.1.3 Structure and mechanism
• 3.2.1.4 lsoforms and expression in the plant
• 3.2.1.5 Regulation
• 3.2.2 V-ATPases
• 3.2.2.1 Physiological role
• 3.2.2.2 Genetics
• 3.2.2.3 Structure and mechanism
• 3.2.2.4 Isoforms and expression in the plant
• 3.2.2.5 Regulation
• 3.2.3 Vacuolar pyrophosphatase
• 3.2.3.1 Physiological role
• 3.2.3.2 Structure and mechanism
• 3.2.3.3 Isoforms and expression in the plant
• 3.2.3.4 Regulation
• 3.3 Calcium pumps in plant cells
• 3.3.1 Calcium in plant cells
• 3.3.2 Ca2+-ATPases (P2 ATPases)
• 3.3.2.1 Physiological role
• 3.3.2.2 Genetics
• 3.3.2.3 Structure and mechanism
• 3.3.2.4 Isoforms and expression in the plant
• 3.3.2.5 Regulation
• 3.4 Other plant cation pumps
• Acknowledgements
• References
• 4 Ion-coupled transport of inorganic solutes
• 4.1 Introduction
• 4.1.1 Ion gradients and ion-coupled transport mechanisms
• 4.1.2 Thermodynamics of ion-coupled transport
• 4.1.3 Determining the feasibility of co-transport mechanisms
• 4.1.4 Functions and relationships to physiology
• 4.1.5 Targeting and membrane location
• 4.1.6 Transporter expression and nutrient availability
• 4.2 Types of ion-coupled transporter
• 4.3 Nitrate
• 4.3.1 Physiology of nitrate transport mechanisms
• 4.3.2 Nitrate transporter gene families
• 4.3.3 Regulation of expression
• 4.3.4 Function in the root
• 4.3.5 Function in the leaf
• 4.4 Sulphate
• 4.4.1 The sulphate transporter gene family
• 4.4.2 Functional characterization
• 4.4.3 Regulation
• 4.5 Ammonium
• 4.5.l NH4+ uptake gene family
• 4.5.2 Function in the root
• 4.5.3 Function in the leaf
• 4.6 Energetic costs of transport
• 4.6.1 Nitrate and sulphate efflux
• 4.6.2 Ammonium efflux
• 4.7 Conclusions and future research
• 4.7.1 Gene families and functional diversity
• 4.7.2 Homeostasis of cell nutrients and nutrient sensors
• 4.7.3 Conclusions
• Acknowledgements
• References
• 5 Functional analysis of proton-coupled sucrose transport
• 5.1 Introduction
• 5.2 Defining basic properties of transport
• 5.3 Intact tissues
• 5.4 Membrane vesicles
• 5.5 Sucrose sensing
• 5.6 Heterologous expression systems
• 5.7 Sucrose transport in plant growth and development
• 5.7.1 Patterns of gene expression
• 5.7.2 Antisense expression and gene knockouts in transgenic plants
• References
• 6 Voltage-gated ion channels
• 6.1 Introduction
• 6.2 Voltage gating from a mechanistic point of view
• 6.2.1 Static - steady-state equilibrium
• 6.2.2 Kinetic - relaxation into an equilibrium
• 6.2.3 Comparison of the model with the in vivo situation
• 6.3 Voltage-gated ion channels uncovered in plants and their involvements in physiological processes
• 6.3.1 Plasma membrane potassium channels
• 6.3.1.1 Hyperpolarisation-activated K+ channels - Kin channels
• 6.3.1.2 Depolarisation-activated K+ channels - Kout channels
• 6.3.1.3 Weakly rectifying K+ channels - Kweek channels
• 6.3.2 Vacuolar potassium channels
• 6.3.2.1 Slow-activating vacuolar channel
• 6.3.2.2 Fast-activating vacuolar channel
• 6.3.2.3 Vacuolar K+ channels
• 6.3.3 Plasma membrane calcium channels
• 6.3.3.1 Hyperpolarisation-activated Ca2+ channels
• 6.3.3.2 Depolarisation-activated Ca2+ channels
• 6.3.4 Vacuolar calcium release channels
• 6.3.5 Calcium channels in the endoplasmatic reticulum
• 6.3.6 Plasma membrane anion channels
• 6.3.6.1 Depolarisation-activated anion channels
• 6.3.6.2 Inward-rectifying anion channels
• 6.3.7 Vacuolar anion channels
• 6.4 Gating modifiers
• 6.4.1 Phosphorylation
• 6.4.2 Nitrosylation and other redox reactions
• 6.4.3 Calcium ions
• 6.4.4 Protons
• 6.4.4.1 Cytosolic pH changes
• 6.4.4.2 Extracellular/luminal pH changes
• 6.4.5 Potassium ions
• 6.4.6 Anions
• 6.4.7 Phytohorrnones
• 6.4.7.1 Auxins
• 6.4.7.2 Abscisic acid
• 6.4.8 Lipids and their hydrolysis products
• 6.4.9 Proteins and peptides
• 6.4.9.1 G-proteins
• 6.4.9.2 14-3-3 Proteins
• 6.4.9.3Calmodulin
• 6.5 Outlook - voltage-gated ion channels in ‘Systems Biology’
• References
• 7 Ligand-gated ion channels
• 7.1 Introduction
• 7.2 Acetylcholine receptors, the archetypal ligand-gated ion channels
• 7.3 Techniques to study ligand-gated channels
• 7.4 Plant ligand-gated ion channels
• 7.5 Ca2+ release channels from endomembranes
• 7.5.1 IP3-gated channels
• 7.5.2 cADPR-gated channels
• 7.5.3 NAADP-gated channels
• 7.6 Non -selective ligand-gated ion channels
• 7.6.1 Glutamate receptors
• 7.6.2 Cyclic-nucleotide-gated channels
• 7.7 Concluding remarks
• References
• 8 Aquaporins in plants
• 8.1 Introduction
• 8.2 Water transport measurements: principles and methods
• 8.2.1 Theory
• 8.2.2 Stopped-flow techniques
• 8.2.3 Swelling of isolated cells, protoplasts and vacuoles
• 8.2.4 The pressure probe technique
• 8.2.5 Water transport measurements on excised organs
• 8.2.6 Nuclear magnetic resonance techniques
• 8.3 Aquaporins at the level of molecules, cells and tissues
• 8.3.1 Classification of plant aquaporins
• 8.3.2 Molecular level: a variety of selectivity profiles
• 8.3.2.1 Transport selectivity
• 8.3.2.2 Aquaporin structure and molecular basis of aquaporin selectivity
• 8.3.2.3 Significance of CO2 transport
• 8.3.3 Cell level: subcellular targeting
• 8.3.3.1 Pattern of aquaporin expression within the cell
• 8.3.3.2 Role of aquaporins in cell osmoregulation
• 8.3.4 Tissue level: the role of aquaporins in root water uptake
• 8.3.4.1 Cell-specific expression patterns
• 8.3.4.2 Role of cell membranes and aquaporins in water uptake
• 8.4 Mechanisms of regulation
• 8.4.1 Levels of regulation
• 8.4.2 Regulation of gene expression
• 8.4.3 Protein translation and degradation
• 8.4.4 Protein targeting
• 8.4.5 Molecular mechanisms of aquaporin gating
• 8.4.5.1 Regulation by phosphorylation
• 8.4.5.2 Regulation by protons
• 8.5 Conclusion
• Reference
• 9 Ca2+ and pH as integrating signals in transport control
• 9.1 Introduction
• 9.2 Transport and the control of development
• 9.3 Plant and algal transporters and tip-growth control
• 9.4 Tip growth shows oscillations in fluxes and growth
• 9.5 How are local Ca2+ gradients formed1
• 9.6 G-proteins regulating ion fluxes at the apex
• 9.7 Regulation of H+ fluxes
• 9.8 Transport and the reversible control of cell volume
• 9.9 The mechanistic basis of reversible cell volume change
• 9.10 Calcium and volume change in motor cells
• 9.11 Ca2+, secretion and the cytoskeleton
• 9.12 How are Ca2+ oscillations generated?
• 9.13 G-proteins regulating signaling in guard cells
• 9.14 Regulation of + fluxes
• 9.15 Roles of extracellular Ca2+ and pH in wall structure/activity of guard cells and pulvinar cells
• 9.16 Conclusions and perspectives
• Acknowledgements
• References
• 10 Vesicle traffic and plasma membrane transport
• 10.1 Introduction
• 10.2 Membrane turnover in plants
• 10.3 Turnover of membrane proteins
• 10.3.1 Cycling and redistribution of PIN
• 10.3.2 Cycling of K+ channels in guard cells
• 10.3.3 Auxin-induced channel expression in elongating cells
• 10.4 Parallels to mechanisms in animal cells
• 10.5 Regulatory mechanisms in membrane trafficking and their implications for activity of ion transport proteins
• 10.5.1 ER export as control step in surface expression of ion channels
• 10.5.2 Ca2+ and exocytosis
• 10.5.3 Membrane tension and exo- and endocytosis
• 10.5.4 SNARE proteins and their possible role in ion channel trafficking and gating
• Acknowledgements
• References
• 11 Potassium nutrition and salt stress
• 11.1 The physiology of potassium nutrition and salt stress
• 11.1.1 The physiology of potassium nutrition
• 11.1.l.1 Roles of potassium in the plant
• 11.1.l.2 Symptoms of potassium starvation and impact on agriculture
• 11.1.l.3 Potassium mutants
• 11.1.l.4 Potassium homeostasis
• 11.1.2 The physiology of salt stress
• 11.1.2.1 The problem with salt
• 11.1.2.2 Sodium toxicity
• 11.1.2.3 Sodium mutants
• 11.1.2.4 Sodium homeostasis
• 11.2 Setting the scene for K+ and Na+ transport
• 11.2.1 Driving forces for K+ and Na+ movement across membranes
• 11.2.2 Tissues and membranes involved in K+ and Na+ transport
• 11.3 Functional genomics of K+ and Na+ transport: linking experimental evidence
• 11.4 Functional types of transporters involved in K+ homeostasis and salt stress
• 11.4.1 Transport pathways for K+ and Na+
• 11.4.1.1 Voltage-dependent channels
• 11.4.1.2 Voltage-independent channels
• 11.4.1.3 Genes encoding cation-selective channels
• 11.4.1.4 Active transport of K+ and Na+
• 11.4.1.5 The KUP/HAK/KT family
• 11.4.1.6 HKT
• 11.4.1.7 Antiporter genes
• 11.4.1.8 Other cation transporters
• 11.4.2 Providing the driving force for K+ and Na+ transport: proton pumps
• 11.4.3 Other transporters involved in K+ homeostasis and salt stress
• 11.4.3.l ABC transporters
• 11.4.3.2 Aquaporins
• 11.5 Regulation and integration of K+ and Na+ transport
• 11.5.l Perception of K+ and Na+
• 11.5.2 Intracellular signalling of cation stress
• 11.5.2.1 Cytoplasmic Ca2+, kinases and phosphatases
• 11.5.2.2 Cyclic nucleotides
• 11.5.2.3 Other regulators of ion transport
• 11.5.3 Hormonal control of ion homeostasis
• 11.5.3.1 Abscisic acid
• 11.5.3.2 Jasmonic acid and polyamines
• 11.6 Future prospects
• 11.6.1 Technologies
• 11.6.2 Model plants
• 11.7 Concluding remarks
• References
• 12 Membrane transport and soil bioremediation
• 12.1 Introduction
• 12.2 Phytostabilisation
• 12.2.1 Root exudation
• 12.2.2 Enrichment of microbial degraders
• 12.2.3 Enhancement of microbial biodegradation activity
• 12.2.4 Mechanisms of exudation
• 12.3 Phytoextraction
• 12.3.1 Uptake of heavy metals from the rhizosphere
• 12.3.2 Formation and transport of intracellular chelates
• 12.3.3 Transport to the shoot
• 12.3.4 Distribution and compartmentation in the shoot
• 12.4 Discussion
• References
• Index