Biological cell membranes regulate the transfer of matter and informa tion between the intracellular and extracellular compartments as basic survival and maintenance functions for an organism: This volume contains a series of reviews that are concerned with how biological plasma membranes regulate the transport of chloride between the intracellular and extracellular compartments of a cell. This book is also an attempt to analyze the molecular basis for the movement of chloride across a cell membrane. This volume is devoted to a diversity of electrogenic chloride transport mechanisms in representative cell membranes of all living things. The first section of the book (Chaps. 1-4) focuses on mech anisms of primary active chloride transport (i.e. photon or A TP-driven), while the second section (Chaps. 5-6) centers on secondary active chloride transporters (symport and antiport) in both plant and animal plasma membranes. The last section, which comprises seven chapters (Chaps. 7-13), deals with chloride channels in cell membranes of prokaryocytes and eukaryocytes of most every phylum. It is hoped that with this particular ordering the reader can glean a telescopic view of the evolutionary history of the various electrogenic chloride transporters.

1 Halorhodopsin: A Prokaryotic Light-Driven Active Chloride Transport System

1 Introduction
2 Anion Binding and the Retinal Chromophore as Reporter Group
3 The Photocycle
4 Light-Dependent Retinal Isomerizations and Schiff Base Deprotonation
5 Hypotheses of the Transport Mechanism
References
2 Chloride ATPase in Marine Algae
1 Introduction
2 Objects
3 Some Conditions
4 Basic Observations: The Pump and Its Transportée
5 Fueling Substrate
6 Electrical Properties
7 Biochemical Approaches
8 Conclusions and Speculations
References
3 Existence of a Chloride Pump in Molluscs
1 Introduction
2 Electrical Characteristics of Aplysia Gut
3 Biochemistry of the Cl? Pump
4 Sulfhydryl Ligands of the Cl? Pump
5 Reconstitution of the Cl? Pump
6 Molecular Weight and Reaction Sequence of the Cl? Pump
7 Conclusions
References
4 Transporting Cl?-ATPase in Rat Brain
1 Introduction
2 Cl?-Stimulated ATPase in Mammalian Brain
3 Functional Significance of Cl? Pump in the Brain
4 Conclusions
References
5 Proton-Coupled Chloride Transport in Plant Cells
1 Introduction
2 Evidence for Gradient-Coupled Cl? Transport
3 Kinetic Properties of Gradient-Coupled Cl? Transport at the Plasma Membrane
4 Conclusions and Future Prospects
References
6 Electrogenic Coupling of Sulfate Secretion to Chloride Transport in Lobster Hepatopancreas
1 Introduction
2 Vertebrate Sulfate Transport Mechanisms
3 Transmembrane SO4/C1 Exchange in Vertebrate Epithelia
4 Transmembrane Sulfate Antiport in Hepatopancreatic Epithelium
5 Transcellular Sulfate Transport in Lobster Hepatopancreas
References
7 Chloride Currents in Lower Organisms
1 Introduction
2 Protists
3 Porifera
4 Cnidaria
5 Platyhelminths
6Nematodes
7 Discussion
References
8 Chloride Channels in Molluscs
1. Introduction
2. Excitable Cell Cl? Channels
3. Aplysia Gut Absorptive Cells
References
9 Chloride Channels in Insects: A Search for Common Grounds
1 Introduction
2 Defining Characteristics of Vertebrate Epithelial Cl? Channels
3 Cl? Channels in Insect Epithelial Secretion and Absorption
4 GABA-Activated Cl? Channel in Nervous System and Muscle
5 Conclusions
References
10 The Voltage-Gated Cl? Channel of Torpedo Electroplax: an Emerging View of its Structure and Function
1 Introduction
2 Electrocyte Physiology
3 Biophysics of the Cl? Channel
4 Biochemical Studies
5 Molecular Genetics of the Cl? Channel
6 Conclusion
References
11 A Secretory Cl Channel from Epithelial Cells Studied in Heterologous Expression Systems
1 Introduction
2 Channels Implicated in Transepithelial Chloride Secretion
3 CFTR Expression and Reconstitution Generate the Low-Conductance Cl Channel
4 Properties of the CFTR Pore
5 Regulation of the CFTR Channel by Phosphorylation
6 Regulation of CFTR Channel by Nucleotides
7 Homologs from Other Species: Shark CFTR is also a Cl Channel
8 Conclusions
References
12 Chloride Channels in Epithelial Cells of Intestine
1 Introduction
2 Small Intestine
3 Colon
4 Summary
References
13 Chloride Transport by Gastric Mucosa
1 Introduction
2 Acidic and Nonacidic Cl? Secretion
3 Identification and Localization of Ion Transport Pathways
4 Localization of Passive Ion Transporters
References.