The document discusses protein degradation, highlighting the importance of constant degradation and half-lives of proteins, particularly those that are rapidly degraded and function as regulatory molecules like transcription factors. It outlines signals for degradation, including alterations by oxidation and ubiquitin tagging, and describes the ubiquitin-proteasome pathway and lysosomal proteolysis. The document concludes with multiple-choice questions related to the content covered.

1. PROTEIN DEGRADATION
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2. LIST OF CONTENTS
 Introduction
 Signals for Degradation
 Site of Degradation
 The Ubiquitin- Proteosome pathway
 Lysosomal Proteolysis
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3. INTRODUCTION
Constant degradation
Half lives
Rapidly degrated proteins are
regulatory molecules
E.g Transcription Factors (TF)
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4. CONTINUED …
In Lysosomes and cytosol
Signals for degradation
• Protein function
• Proteins altered by oxidation
• Tagged by ubiquitin
• N terminal
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5. THE UBIQUITIN- PROTEOSOME
PATHWAY
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6. A COMPARISON
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LYSOSOMAL
PROTEOLYSIS UBIQUITIN
PROTEOSOM
E PATHWAY

7. THANK YOU
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8. MCQS
 Many rapidly degraded proteins function as
regulatory molecules, such as ______
a) Transcriptions factors b) histones c)
silencers d) proteases
 The major pathway of selective protein degradation
in eukaryotic cells uses_____as marker
a) Ubiquitin b) protease c) beta subunit
d ) lysosome
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