Unit 3107: Cellular Signaling

1. Introduction to Cellular Signaling

• Overview of cellular signaling
• Types of signaling molecules (e.g., hormones, neurotransmitters, cytokines)
• Importance of cell communication in multicellular organisms
• General mechanisms of signal transduction

2. Types of Cell Signaling

• Autocrine signaling: cells signaling to themselves
• Paracrine signaling: local signaling to nearby cells
• Endocrine signaling: hormone-mediated long-distance signaling
• Direct cell-to-cell communication: gap junctions and cell adhesion molecules
• Biological significance and examples of each type

3. Cell Surface Receptors

• Overview of receptor function in signal perception
• G-protein Coupled Receptors (GPCRs)
  • Structure and activation mechanism
  • Role in diverse physiological processes
• Receptor Tyrosine Kinases (RTKs)
  • Structure and ligand binding
  • Autophosphorylation and downstream signaling
• Ion Channel Receptors
  • Types (ligand-gated, voltage-gated)
  • Function in rapid signaling

4. Intracellular Signaling Pathways

• MAPK (Mitogen-Activated Protein Kinase) Pathway
  • Cascade components and activation
  • Role in cell growth and differentiation
• PI3K/Akt Pathway
  • Activation and function
  • Regulation of cell survival and metabolism
• JAK/STAT Pathway
  • Cytokine receptor signaling mechanism
  • Influence on gene transcription

5. Second Messengers

• Definition and importance in signal amplification
• Cyclic AMP (cAMP)
  • Production and role in signaling
• Inositol Triphosphate (IP3)
  • Generation and function in calcium release
• Calcium ions (Ca2+)
  • Role as a versatile second messenger
  • Mechanisms of intracellular calcium regulation

6. Signal Transduction and Gene Expression

• Transmission of signals from membrane to nucleus
• Activation of transcription factors (e.g., NF-κB, CREB)
• Regulation of gene transcription and protein synthesis
• Examples linking signaling to cellular responses

7. Crosstalk in Cell Signaling

• Concept of signaling pathway crosstalk
• Mechanisms enabling integration of multiple signals
• Examples of crosstalk regulating physiological processes
• Importance in maintaining cellular homeostasis

8. Dysregulation of Cell Signaling in Disease

• Aberrant signaling and disease pathogenesis
• Examples:
  • Cancer: mutations in RTKs and downstream effectors
  • Diabetes: insulin signaling defects
  • Autoimmune disorders: dysregulated cytokine signaling
• Therapeutic strategies targeting signaling molecules
  • Small molecule inhibitors
  • Monoclonal antibodies

9. Emerging Trends in Cellular Signaling Research

• Computational modeling of signaling networks
• Single-cell analysis techniques
• Optogenetics for precise control of signaling
• Implications for precision medicine and novel therapeutics