The Regulation of Cell Death: APOPTOSIS Presented by: Jesse Kemp

Introduction and Overview Death Due to External Source or Injury vs. Death by Committing Suicide Why Is There a Need For This Type of Pathway? Causes of Apoptosis Mechanism of Apoptosis

Death by External Source or Injury Toxin Damage Mechanical Damage Uncontrolled Swelling Leakage of Cell Contents Resulting Inflammation of Surrounding Tissue

Death by Committing Suicide While committing suicide cells: Shrink Chromatin Degraded Mitochondria Break Down Break into Membrane-bound Fragments Phosphatidylserine Exposed Phagocytic Receptors Inflammation Inhibition

Purpose for this Pathway! Apoptosis is needed for: Proper Development of the Organism ex) Formation of Fingers and Toes ex) Resorption of the Tadpole Tail during Metamorphosis Destruction of Cells that Pose a Potential Threat to the Organism ex) Cells Infected with Viruses ex) Cells of the Immune System ex) Cancerous Cells

Balancing Act Within Every Organism, there is a Continual Battle Fought Between the Withdraw of Positive Signals and the Receipt of Negative Signals Positive Signals Negative Signals

Mechanism of Apoptosis 3 Different Pathways Internal (Mitochondrial) Pathway External (Death Receptor) Pathway Non-Caspase Pathway

Internal (Mitochondrial) Pathway

Alternate Pathways External Pathway (Death Receptor) Fas and TNF Receptor Death Activator (FasL) Caspase 8 Phagocytosis Ex) Cytotoxic T Cells Non-Caspase Pathway AIF Released from Mitochondria Migration to the Nucleus DNA Binding

Conclusion Sources of Cell Death Need for the Apoptosis Pathways Causes of Apoptosis Mechanisms of Apoptosis

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