Protein Phosphatases and Stress Management in Plants: Functional Genomic Perspective

Preface
Contents
Author’s Biography
Chapter 1: SLP1 and SLP2: Ancient Chloroplast and Mitochondrial Protein Phosphatases
	1.1 Introduction
	1.2 Protein Phosphatases in Eukaryotes
	1.3 Chloroplast and Mitochondrial Protein Phosphorylation
	1.4 Discovery and Bioinformatics of SLP1 and SLP2
	1.5 SLP1 Is a Chloroplast-Localized Serine/Threonine Protein Phosphatase
	1.6 SLP2 Is a Mitochondrial Intermembrane Space Serine/Threonine Protein Phosphatase
	1.7 Mia40 as a Redox Regulator
	1.8 MS-Based Substrate Discovery: The Future of Protein Phosphatases?
	1.9 Conclusions
	References
Chapter 2: Phosphoprotein Phosphatase Function of Secreted Purple Acid Phosphatases
	2.1 Introduction
		2.1.1 PAPs Play a Central Role in Plant Pi Acquisition and Use Efficiency
	2.2 Extracellular Protein Phosphorylation Networks of Animals and Plants: The Neglected PTM
		2.2.1 Animals
		2.2.2 Plants
	2.3 Phosphoprotein Phosphatase Function of Secreted PAPs
		2.3.1 Animals
		2.3.2 Plants
	2.4 Plant Haloacid Dehalogenase-Like APases May Function as Cytoplasmic Phosphoprotein Phosphatases
	2.5 Concluding Remarks
	References
Chapter 3: Purple Acid Phosphatases (PAPs): Molecular Regulation and Diverse Physiological Roles in Plants
	3.1 Introduction
	3.2 Structure and Classification of PAPs
	3.3 PAPs Exist as a Multigene Family
	3.4 Plant PAPs Are Nonspecific Phosphatases
	3.5 Regulation of Purple Acid Phosphatases in Plants
	3.6 Diverse Functions of Plant PAPs
		3.6.1 Organic P Utilization
		3.6.2 Seed Germination and Abiotic/Biotic Stress Tolerance
		3.6.3 Root Architecture Modulation
		3.6.4 Nodule Formation and Arbuscular Mycorrhizal (AM) Symbiosis
		3.6.5 Regulation of Flowering
		3.6.6 Seed Development
	3.7 Future Perspectives
	References
Chapter 4: Role of Serine/Threonine Phosphatase PP2A Class and Its Regulators in Salinity Stress Tolerance in Plants
	4.1 Introduction
	4.2 Overview of Serine-Threonine Phosphatases in Plants
		4.2.1 Classification of Protein Phosphatases
		4.2.2 Global Functions of PP2A: Diverse Functional Spectrum
		4.2.3 Salinity Stress Sensor Kinases in Plants
		4.2.4 Role of PP2A Holoenzymes in Plants During Salt Stress
	4.3 Concluding Remarks
	References
Chapter 5: Type 2C Protein Phosphatases in Plant Signaling Pathways under Abiotic Stress
	5.1 Introduction
	5.2 Regulatory Targets of PP2Cs in Plant Stress Signaling Pathways
		5.2.1 Core ABA Signaling Module
		5.2.2 Chromatin Remodeling Complex
		5.2.3 MAPK Cascades
		5.2.4 Other Targets
	5.3 Current Studies on PP2Cs in Plant under Abiotic Stress
		5.3.1 Clade A
		5.3.2 Clade B
		5.3.3 Other Clades
	5.4 Conclusion
	References
Chapter 6: Plant Protein Phosphatase 2C: Critical Negative Regulator of ABA Signaling
	6.1 Introduction
	6.2 ABA Signaling: Major Stress Signaling Pathway of Plants
		6.2.1 ABA Receptors: Site for ABA Perception
		6.2.2 Protein Kinases: Positive Regulator of ABA Signaling
		6.2.3 Protein Phosphatase 2C: Negative Regulator of ABA Signaling
		6.2.4 Classification and Evolution of Protein Phosphatases in Plants
		6.2.5 PP2Cs as a Fine Modulator of ABA Signaling
		6.2.6 Clade A PP2Cs and ABA Signaling
		6.2.7 ABA Insensitive 1 and 2 (ABI1 and ABI2)
		6.2.8 ABA Hypersensitive Germination 3 (AHG3/AtPP2CA)
		6.2.9 Hypersensitive to ABA (HAB1)
	6.3 Role of PP2Cs in Various Signaling Pathways in Plants
		6.3.1 PP2Cs in Developmental Signaling
		6.3.2 PP2Cs in Abiotic Stress Signaling
		6.3.3 PP2Cs in Biotic Stress Signaling
	6.4 Conclusions and Future Perspectives
	References
Chapter 7: Protein Phosphatases at the Interface of Sugar and Hormone Signaling Pathways to Balance Growth and Stress Responses in Plants
	7.1 Introduction
	7.2 Structure, Subunit Composition, and General Functions of Protein Phosphatases
		7.2.1 PP2A
		7.2.2 PP2C
	7.3 Sugar as a Signaling Molecule
	7.4 Crosstalk Between Protein Phosphatases and Sugar Signaling
	7.5 Evolutionary Dynamics of Nutrient and Energy Sensing Among Eukaryotes
	7.6 Protein Phosphatases and Interaction with Sugar and ABA in Managing Stress
	7.7 Conclusions and Future Perspective
	References
Chapter 8: Protein Phosphatases in Guard Cells: Key Role in Stomatal Closure and Opening
	8.1 Introduction
		8.1.1 Importance of Stomata
		8.1.2 Signals That Induce Closure/Opening
		8.1.3 Events During Stomatal Closure by ABA
	8.2 Signal Transduction in Guard Cells
		8.2.1 Signal Perception and Transmission
		8.2.2 ABA-Receptor-PP2C Complex Formation
		8.2.3 ABA Analogues Used as Interacting Partners of PP2C/ ABI1
	8.3 Protein Phosphatases (PPs)
		8.3.1 Different Forms of PPs
		8.3.2 PP2C: Essential for Stomatal Closure
		8.3.3 PP2A: Key Component of Stomatal Closure
		8.3.4 PP1: Promotes Stomatal Opening
	8.4 Interacting Partners of PP2C
		8.4.1 ABA Receptors: PYR/PYL/RCAR Proteins
		8.4.2 Protein Kinases Involved in ABA-Mediated Signaling in Guard Cells
		8.4.3 Molecular Interactions of PP2C with PYLs and Kinases
		8.4.4 Arabidopsis Mutants: Versatile Tools to Study the Role of PP2C and PP1 in Stomatal Function
	8.5 Concluding Remarks
	References
Chapter 9: Deciphering the Roles of Protein Phosphatases in the Regulation of Salt-Induced Signaling Responses in Plants
	9.1 Introduction
	9.2 Phosphatases: A Brief Outlook
		9.2.1 PP-1
		9.2.2 PP-2
		9.2.3 PP-4 to PP-7
		9.2.4 Protein Tyrosine Phosphatases (PTPs)
		9.2.5 Phosphatases Which Regulate Inositol Signaling
	9.3 The Roles of Phosphatases in Regulating Salt Stress in Plants
	9.4 Conclusion
	9.5 Future Perspectives
	References
Chapter 10: Phosphatases: The Critical Regulator of Abiotic Stress Tolerance in Plants
	10.1 Introduction
	10.2 Major Protein Phosphatase Gene Families
		10.2.1 Protein Phosphatase P (PPP)
			10.2.1.1 Protein Phosphatase 1
			10.2.1.2 Protein Phosphatase 2A
			10.2.1.3 Protein Phosphatase 2B
			10.2.1.4 PP4, PP5, PP6, and PP7
		10.2.2 Protein Phosphatase M (PPM)
		10.2.3 Protein Tyrosine Phosphatases (PTP)
	10.3 Role of Phosphatases in Abiotic Stress Signaling in Crop Plants
		10.3.1 Salt Stress
		10.3.2 Potassium (K+) Deficiency
		10.3.3 ABA and Stomatal Regulation
		10.3.4 Other Abiotic Stresses
	10.4 Conclusions
	References
Chapter 11: Role of Protein Phosphatases in Signaling, Potassium Transport, and Abiotic Stress Responses
	11.1 Introduction
	11.2 Protein Phosphatases (PPs): Their Classes and Structure
	11.3 The CBL-CIPK Family, Plants Modified Version of PP2B Family Phosphatases
	11.4 Phosphatases and Signal Transduction
		11.4.1 Phosphatases and Abscisic Acid (ABA) Signaling
		11.4.2 Protein Phosphatases in Defense Signaling and the Regulation of Primary and Secondary Metabolism and the Regulation of Mitogen-Activated Protein Kinases (MAPKs)
		11.4.3 Role of Auxin and Brassinosteroid and Protein Phosphatases
	11.5 Conditions that Necessitate K+ Uptake Systems (AKT1, HAK5, KUP7) in Plants and K+ Deficiency Sensing
		11.5.1 Plant Non-voltage-Gated K+ Channels (TPK /KCO) and KEA K+ Transporters
		11.5.2 K+ Deprivation and Calcium Signaling
		11.5.3 Regulation of Arabidopsis K+ Transporter 1 (AKT1) K+ Selective Channel
		11.5.4 Regulation of Arabidopsis K+ Transporter 2 (AKT2) K+ Selective Channels
		11.5.5 Role of Other CBL-CIPK Modules in Ion Homeostasis Pathways
		11.5.6 The GORK and SKOR Channels in K+ Homeostasis and Other Functions in Plant Cell
		11.5.7 The Regulation of AtHAK5
		11.5.8 K+ Uptake Regulation by a Novel CIPK and PP2C Pair
	11.6 Ser/Thr Protein Phosphatases in Stress Adaptation
		11.6.1 Protein Phosphatase Expression Profile Under Stress Conditions
		11.6.2 Phosphatases Are Involved in Modulating Kinases During Salt Stress
		11.6.3 Phosphatases in Regulating Guard Cell: The Best-Characterized ABA Signaling Pathway
	11.7 Conclusions
	References
Chapter 12: Protein Phosphatases in N Response and NUE in Crops
	12.1 Introduction
	12.2 Phosphatases in N Uptake and Primary Nitrate Response
	12.3 PP2Cs Are Negative Regulators of ABA Signaling in NO3− Sensing
	12.4 Phosphatases: Key Players in Carbon and Nitrogen Balance
	12.5 PP2A-TOR in Regulation of Nitrate Metabolism
	12.6 Protein Phosphatases: Fine-Tuning of Nitrate Reductase
	12.7 Phosphatases Identified in N Response/NUE
	12.8 Conclusions and Future Prospects
	References
Chapter 13: Protein Phosphatases of Cereals and Millets: Identification, Structural Organization, and Their Involvement in the Regulation of Abiotic Stresses
	13.1 Introduction
	13.2 Ser/Thr Phosphatases
		13.2.1 Protein Phosphatase 1 (PP1)
		13.2.2 Protein Phosphatase 2A (PP2A)
		13.2.3 Protein Phosphatase 2B (PP2B)/Calcineurin
		13.2.4 Protein Phosphatase 2C (PP2C)
	13.3 Protein Tyrosine (Tyr) Phosphatase
	13.4 Global Identification of Protein Phosphatase in Cereals and Millets
	13.5 Expression Pattern of Protein Phosphatase in Cereals
	13.6 Role of Protein Phosphatases in Abiotic Stress Signaling
	13.7 Concluding Remarks
	References
Chapter 14: Interplay of Protein Phosphatases with Cytoskeleton Signaling in Response to Stress Factors in Plants
	14.1 Introduction
	14.2 The Role of Plant Protein Phosphatases in Stress
	14.3 Dephosphorylation of Serine and Threonine Residues in Plant Stress Response
	14.4 Dephosphorylation of Tyrosine Residues and Its Role in Plant Stress Response
	14.5 The Role of Protein Phosphatases in Cytoskeleton Regulation
	14.6 Conclusion
	References
Chapter 15: Protein Phosphatase Mediated Responses in Plant Host-Pathogen Interactions
	15.1 Prologue
	15.2 Protein Phosphatases in Plant
		15.2.1 Types, Key Features
		15.2.2 Functional Attributes
	15.3 Response of Plant Protein Phosphatases (PPs) Towards Varied Pathogens
		15.3.1 Plant PPs Responding Towards Bacterial Pathogens
		15.3.2 Plant PPs Responding Towards Fungal Pathogens
		15.3.3 Plant PPs Responding Towards Other Known Pathogens
	15.4 Pathogenic Protein Phosphatases Involved in Virulence
		15.4.1 Examples of Bacterial PPs Required for Virulence
		15.4.2 Examples of Fungal PPs Required for Virulence
	15.5 Plant Protein Phosphatases as Targets of Pathogen Maneuvering
	15.6 Conclusion
	References
Chapter 16: Role of Dual Specificity Phosphatase in Stress and Starch Metabolism
	16.1 Introduction
	16.2 Classification of Protein Phosphatases
	16.3 Dual Specificity Phosphatases
		16.3.1 Discovery and Structure of Dual Specificity Phosphatase
		16.3.2 Catalytic Mechanism
	16.4 Roles of Dual Specificity Phosphatase
		16.4.1 Roles of Dual Specificity Phosphatases in Plants
			16.4.1.1 Role in Starch Metabolism
			16.4.1.2 Role in Reactive Oxygen Species Management and Abiotic and Biotic Stresses
				Role in Reactive Oxygen Species Management
				Abiotic Stress
				Biotic Stress
		16.4.2 Roles of Dual Specificity Phosphatases in Animals
	16.5 Conclusions and Future Prospects
	References
Chapter 17: Protein Tyrosine Phosphatases: Implications in the Regulation of Stress Responses in Plants
	17.1 Introduction: Tyrosine Phosphorylation Machinery in Plants
	17.2 Protein Tyrosine Phosphatase: Structure and Catalysis
	17.3 Redox Signaling
	17.4 MAPK Signaling
	17.5 Hormone Signaling Pathways
		17.5.1 Abscisic Acid (ABA) Signaling
		17.5.2 Auxin Signaling
		17.5.3 Brassinosteroid Signaling
	17.6 Developmental Pathways
	17.7 Abiotic Stress Tolerance
	17.8 Biotic Responses
	17.9 Abiotic Stress
	17.10 Conclusion and Future Perspective
	References
Index