Drosophila Eye Development

References.- Retinal Specification and Determination in Drosophila.- 1 Introduction.- 2 Structure and Early Development of the Drosophila Eye.- 3 The Retinal Determination Network.- 3.1 twin of eyeless and eyeless.- 3.2 eyes absent and sine oculis.- 3.3 dachshund.- 4 Retinal Determination Genes: New Members?.- 4.1 teashirt.- 4.2 optix.- 4.3 eyegone.- 4.4 homothorax and extradentscle.- 5 Patterning Genes and Retinal Determination.- 5.1 hedgehog.- 5.2 decapentaplegic.- 5.3 wingless.- 6 Conclusions and Future Directions.- References.- Regulators of the Morphogenetic Furrow.- 1 Introduction.- 2 Notch Activation Defines the Initiation Point.- 3 Hedgehog is Essential for Morphogenetic Furrow Movement.- 4 Decapentaplegic Promotes Morphogenetic Furrow Movement.- 5 Wingless Inhibits Morphogenetic Furrow Movement.- 6 Conclusions.- References.- NOTCH and the Patterning of Ommatidial Founder Cells in the Developing Drosophila Eye.- 1 Introduction.- 2 The Discovery of Ommatidial Founder Cells.- 2.1 Founder Cells for Each Ommatidium.- 2.2 Spacing Patterns, Lateral Inhibition and Notch.- 3 R8 Cell Specification and Patterning.- 3.1 Specification and Differentiation of R8 Precursors.- 3.2 Mechanism of N Signaling During Lateral Inhibition of R8 Precursors.- 3.3 Selection of Particular Cells Within Each Intermediate Group as R8 Precursors.- 4 Intermediate Group Specification and Patterning.- 4.1 Making an Intermediate Group — Proneural Enhancement.- 4.2 Spacing the Intermediate Groups.- 4.3 Role of the EGF Receptor.- 5 Conclusions.- 5.1 Summary of R8 Specification and Patterning.- 5.2 Comparisons with Other Proneural Groups.- References.- The Epidermal Growth Factor Receptor in Drosophila Eye Development.- 1 Introduction.- 2 EGFR Gene Organization, Protein Structure and Mutant Classes.- 3 EGFR Pathway.- 4 Origin and Structure of the Eye.- 5 Eye Specification.- 6 Cell Fate Specification.- 7 Programmed Cell Death.- 8 Concluding Remarks.- References.- Cell Fate Specification in the Drosophila Eye.- 1 Introduction.- 2 Early Events in Cell Fate Specification.- 3 Undifferentiated Cells.- 4 The Precluster.- 4.1 R8 Specification.- 4.2 R2/R5 Specification.- 4.3 R3/R4 Specification.- 5 The Second Wave of Morphogenesis.- 5.1 R1/R6 Specification.- 5.2 R7 Specification.- 5.3 Cone Cell Specification.- 5.4 Pigment Cell Specification.- 6 Generating and Testing Combinatorial Models.- References.- Tissue Polarity in the Retina.- 1 Tissue Polarization in Development.- 1.1 What Is Tissue Polarity?.- 1.2 Why Is the Retina Polarized?.- 2 The Arrangement of the Ommatidia Within the Plane of the Retina.- 2.1 Establishment of Ommatidial Polarity During Development.- 2.2 The Role of the R3 and R4 Photoreceptors in Ommatidial Polarization.- 3 Genetic Control of Retinal Polarization.- 3.1 The “Tissue Polarity” or Planar Polarity Genes.- 3.2 Frizzled and Dishevelled.- 3.3 A Frizzled Mediated Planar Polarity Signaling Pathway Is Emerging.- 3.4 How Is Frizzled Activity Regulated?.- 3.5 Other Primary Polarity Genes Involved in Retinal Polarity.- 4 How Is the Polarity Signal Interpreted Within a Single Ommatidium?.- 5 Ommatidial Rotation.- 6 General Conclusions.- References.- Regulation of Growth and Cell Proliferation During Eye Development.- 1 Introduction.- 2 Growth and Cell Proliferation During Eye Development.- 3 Mechanisms That Regulate Imaginal Disc Growth.- 3.1 Disc Autonomous Mechanisms That Regulate Growth.- 3.2 Non-Autonomous Control of Disc Growth.- 3.3 Signaling Pathways Regulating Imaginal Disc Growth.- 3.3.1 PI-3 Kinase Pathway.- 3.3.2 Myc.- 3.3.3 Ras/MAPK.- 3.3.4 Cyclin D/cdk4.- 3.3.5 Tscl and Tsc2.- 3.3.6 Drosophila “Tumor-Suppressor” Genes.- 3.3.7 Non-Autonomous Regulators of Growth.- 4 Mechanisms That Regulate Growth and Cell Proliferation in the Eye-Imaginal Disc.- 4.1 Cell Proliferation in First and Second Larval Instar Discs.- 4.2 Cell Proliferation in the Anterior Domain of the Third-Instar Discs.- 4.3 Synchronization of Cells in the Morphogenetic Furrow.- 4.4 Regulation of the Second Mitotic Wave.- 4.5 Exit from the Cell Cycle.- 4.6 Post-Mitotic Growth of the Eye.- 5 Connections Between Disc Patterning and Growth.- 5.1 Lessons from the Wing Disc.- 5.2 Patterned Growth in the Eye Disc; Notch and Morphogen Gradients.- 5.3 Growth Control by Other Patterning Factors.- 5.4 Influence of the Peripodial Membrane.- 5.5 Interactions Between Patterning Networks and Growth Pathways.- 6 Concluding Remarks.- References.- Evolution of Color Vision.- 1 The Retinal Mosaic of the Compound Eye.- 1.1 Rhabdomere and Photoreception.- 1.2 Image Formation and Neural Superposition.- 1.3 Ocelli.- 2 Photoreceptors and Visual Pigments.- 2.1 Color Vision.- 2.2 Evolution and Properties of Rhodopsins.- 2.3 Polarized Light Vision.- 3 Spectral Organization of the Fly Retina.- 3.1 Inner Photoreceptors and Color Vision.- 3.2 Yellow and Pale Ommatidia.- 3.3 Regulation of Rhodopsin Expression.- References.- Developmental Regulation Through Protein Stability.- 1 Introduction.- 2 The Ubiquitin/Proteasome Pathway.- 3 Regulation of Ttk88 Protein Stability.- 3.1 Sina and Phyl Regulate Ttk88 Stability.- 3.1.1 Genetic Evidence.- 3.1.2 Biochemical Evidence.- 3.1.3 Involvement of UbcDl.- 3.2 Ebi, an E3, Also Controls Ttk88 Degradation.- 4 Control of Cell Communication by Faf, a Ubp.- 4.1 Faf Prevents the Mystery Cells from Becoming R-Cells.- 4.1.1 Faf Functions Outside R-Cells.- 4.1.2 Faf Indirectly Downregulates Egfr Activity in R-Cells.- 4.2 Faf Activity Antagonizes Ubiquitination and Proteolysis.- 4.3 The Key Substrate of Faf May Be Lqf, Drosophila Epsin.- 4.4 Faf Activity Facilitates Endocytosis.- 4.5 Faf Also Has a Redundant Function in Eye Development.- 4.6 Models for the Faf Pathway.- 5 Future Directions.- References.- Programmed Death in Eye Development.- 1 Introduction.- 2 Downstream Components: Molecules of Death.- 3 Adaptive Apoptosis: DNA Damage.- 4 Upstream Signals: Death Decisions in the Fly Eye.- 5 Morphogenesis of Lattice Patterning: Making a Hexagon.- 6 Retinal Degeneration.- 6.1 Loss of Trophic Support.- 6.2 Phototransduction Mutants.- 7 Concluding Remarks.- References.- Drosophila Compound Eye Morphogenesis: Blind Mechanical Engineers?.- 1 Introduction.- 2 Morphogenic Forces Are Grounded in Epithelial Tension.- 3 Apical Cell-Cell Contacts.- 4 Apical-ECM Contacts.- 5 Basal-ECM Contacts.- 6 Rhabdomere Morphogenesis.- 7 The Rhabdomere Terminal Web.- 8 Constrained Expansion.- 9 Conclusion.- References.- The Establishment of Retinal Connectivity.- 1 Introduction.- 2 The Structure of the Adult Visual System.- 3 The Development of the Photoreceptor Projection.- 4 Anterograde Signals: Incoming Retinal Fibers Trigger Target Cell Development.- 5 Retrograde Signals.- 5.1 Retinotopic Map Formation.- 5.2 Axon Guidance and Target Layer Selection.- 6 Signal Transduction in Photoreceptor Axon Growth Cones.- 7 Outlook.- References.- Homologies Between Vertebrate and Invertebrate Eyes.- 1 Eye Field Topology.- 1.1 Definition of the Anterior Brain/Eye Anlage.- 1.2 Topology of the Anterior Brain/Eye Anlage.- 2 The Expression Pattern of Regulatory Genes.- 3 Signaling Pathways That Partition the Eye Field.- 4 Eye Morphogenesis.- 4.1 Drosophila Visual System: Embryonic and Early Larval Development.- 4.2 Drosophila Visual System: Adult Eye Differentiation.- 4.3 Vertebrate Eye Morphogenesis.- 5 Retinal Differentiation.- 5.1 Homology of Cell Types in the Vertebrate Retina to the Drosophila Eye.- 5.2 Ganglion Cells Differentiate in a Regular Array in the Developing Chick Retina.- 5.3 How is the Wave of Ganglion Cells Initiated and Propagated?.- 5.4 Molecular Mechanisms of Ganglion Cell Differentiation.- 5.5 Are the Mechanisms of Photoreceptor Differentiation Conserved?.- 6 Evolution and Homologies.- References.- Applications of the Drosophila Retina to Human Disease Modeling.- 1 Introduction.- 2 Classic Forward Genetics in the Drosophila Retina.- 2.1 Eye Specification Genes.- 2.2 Developmental Signaling Pathway Mutants.- 3 Phototransduction Cascade Mutants.- 4 Creating Directed Models for Human Disease.- 4.1. Polyglutamine Expanded Repeat Disease.- 4.1.1 Modeling the Disease in the Drosophila Retina.- 4.1.2 Defining Modifiers of Polyglutamine Disease Using Drosophila Genetics.- 4.2 Applications to Parkinson’s Disease.- 4.3 Alzheimer’s Disease-Related Presenilin.- 5 Concluding Remarks.- References.