How Protein Degradation begins in organisms?What are the signals involve?and what about the site of protein degradation?

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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