1;Preface;5 2;Obituary;6 3;List of Contents;8 4;List of Contributors;9 5;Gene Regulatory Networks Orchestrating B Cell Fate Specification, Commitment, and Differentiation;10 5.1;1 Introduction;10 5.2;2 Specification and Commitment to the B Cell Fate;11 5.3;3 Regulation of Ig Gene Rearrangement and Pre-B Cell Differentiation;17 5.4;4 Conclusions and Perspectives;19 5.5;References;19 6;Helix-Loop-Helix Proteins in Lymphocyte Lineage Determination;23 6.1;1 Introduction;23 6.2;2 E2A Proteins;25 6.3;3 Class VI HLH Proteins: Hes-1/5;28 6.4;4 Id Proteins;28 6.5;5 Conclusions and Future Directions;29 6.6;References;32 7;Ikaros-Family Proteins: In Search of Molecular Functions During Lymphocyte Development;36 7.1;1 Introduction;37 7.2;2 Discovery;37 7.3;3 Structure and Family Members;38 7.4;4 Genetics;40 7.5;5 Localization to Centromeric Heterochromatin;42 7.6;6 Centromere Structure and Function;44 7.7;7 Centromere Role During Interphase;46 7.8;8 Potential Ikaros Functions at Pericentromeric Heterochromatin;47 7.9;9 Future Directions;49 7.10;References;50 8;Biochemistry of V(D)J Recombination;55 8.1;1 Introduction;56 8.2;2 DNA Transactions in V(D)J Recombination;59 8.3;3 Proteins That Mediate V(D)J Recombination;60 8.4;4 Recent Insights from In Vitro Cleavage Studies;68 8.5;5 Sequence-Specific Binding of the Recombination Signal by RAG1 and RAG2;73 8.6;6 Future Prospects;81 8.7;7 Epilogue;82 8.8;References;84 9;The pre-B cell Receptor in B Cell Development: Recent Advances, Persistent Questions and Conserved Mechanisms;92 9.1;1 Introduction;93 9.2;2 Commitment to the B Cell Lineage;94 9.3;3 The Development of Pre-B Cells;95 9.4;4 Initiating Signals Through the Pre-BCR;96 9.5;5 Different Signals for Different Functions;99 9.6;6 The Pre-TCR and Pre-BCR: Conservation of Signaling Properties and Functions?;101 9.7;7 Final Comments;102 9.8;References;103 10;Transcriptional Control of B Cell Activation;109 10.1;1 Introduction;110 10.2;2 Octamer-Binding Proteins and Cofactors;113 10.3;3 Rel-NF- kB Family Proteins;118 10.4;4 Pax-5/BSAP;123 10.5;5 Ets-1 Family Proteins;125 10.6;6 Ikaros Family Proteins;128 10.7;7 NF-AT Family Proteins;129 10.8;8 Other Transactivators Implicated in B Cell Activation;130 10.9;9 Concluding Remarks;134 10.10;References;136 11;Expression of MHC II Genes;151 11.1;1 Innate and Adaptive Immunity;152 11.2;2 Class II Transactivator;161 11.3;3 Conclusions and Future Directions;169 11.4;References;170 12;Class Switch Recombination: An Emerging Mechanism;175 12.1;1 Introduction;176 12.2;2 Overview of CSR;177 12.3;3 A Model for the Initiation and Resolution Steps in CSR;179 12.4;4 CSR and SHM Uncoupled;188 12.5;5 Genome Instability Syndromes and CSR;189 12.6;6 Targeting Mechanisms in CSR;191 12.7;7 Concluding Remarks;197 12.8;References;198 13;Blimp-1; Immunoglobulin Secretion and the Switch to Plasma Cells;204 13.1;1 Plasma Cell Biology;205 13.2;2 Transcriptional Regulation of Ig Secretion;208 13.3;3 Blimp-1-Regulated Maturation Program;212 13.4;4 Post-translational Regulation of Ig Secretion;220 13.5;5 Remarks and Future Directions;222 13.6;References;224 14;Wnt Signaling in Lymphopoiesis;228 14.1;1 Overview of the Different Wnt Signaling Pathways;229 14.2;2 The Canonical Wnt Signaling Pathway;230 14.3;3 Biochemical and Biological Properties of LEF/TCF Proteins;232 14.4;4 Activation of LEF1/TCF Function by b- Catenin and Other Cofactors;235 14.5;5 Transcriptional Repression and Inhibition of LEF1/TCF Function;237 14.6;6 Hematopoiesis;238 14.7;7 Role of the Wnt Pathway in Hematopoietic Stem Cells;240 14.8;8 Role of Wnt Signaling in Pro-B cell Proliferation and Survival;241 14.9;9 Role of Wnt Signaling in T Cell Development;243 14.10;10 Role of LEF/TCF in NK Cell Development;246 14.11;11 Concluding Remarks;247 14.12;References;247 15;Subject Index;256