This document discusses protein folding and the role of chaperone proteins. It notes that heat shock proteins are a highly conserved group of proteins found in both eukaryotic and prokaryotic cells that are involved in many cellular processes. These heat shock proteins are classified by molecular weight and include Hsp70, Hsp90, Hsp60 and small heat shock proteins. The document outlines several important chaperone systems in protein folding, including Hsp70 with its co-chaperones DnaJ and GrpE, and the chaperonin systems of GroEL/GroES and TRiC. It describes the three stages that chaperones use to fold proteins: preventing aggregation, releasing proteins for

1. Chaperone and Protein
folding
Ali Hamrahi
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2. Overview
Conformation of
Protein
Chaperones
Chaperonins
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3. HEATSHOCK
PROTEINS
 are a group of highly conserved proteins
 found in both eukaryotic and prokaryotic cells
 involved in a wide range of cellular processes
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4. DifferentTypes of
HeatShock
Proteins
 Heat Shock Proteins are classified by their molecular
weight, size, structure, and function.
Hsp sHsp
Hsp90 Hsp20
Hsp70 Hsp27
Hsp60 Crystallin alpha beta
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5. Two types of
enzyme
activity may
be used to
create native
protein
conformation
 PDI Protein Disulfide Isomerase
 PPI Peptide Prolyl sis-trans Isomerase
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6. ImportantChaperones
Systems in Protein Folding
Hsp70
DnaJ / Hsp4o
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7. Hsp70Chaperone
Two domains
ATPase
In bacteria DnaK co Factor DnaJ & GrpE
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Hsp70 Reaction in
Polypeptide binding

8. ChaperoninsSystem
ATAase
GroEL (Hsp60)
TRiC
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9. Therearethreestages
forthefoldingof
proteinsby
chaperones
▪ Prevent aggregation by binding to
unfolded polypeptides or
polypeptides that are partially
folded
▪ Releasing unfolding polypeptides
to the folding part
▪ Reconnecting and restoring the
polypeptides that failed in folding
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10. GroEL
&
GroES
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11. GroEL-GroESATPaseCycle
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12. group II chaperonins ; TRiC
 In Archaebacteria and Eukaryote
 3 domains
 2 rings and 8-9 subunit
 Unlike GroEL, most group II chaperonins are heteromeric.
 Without GroES
 Need to co-Chaperon (Gimic)
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13. The main
role ofTRiC
is the folding
of essential
proteins
Actin
Tubulin
Cyclin E
Cdc20
Tumor inhibitor ProteinVHL
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14. Structural
comparison of
group I and
group II
chaperonins.
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15. Disease
15
The Role of Hsp
in Disease

16. Hsp and CNS
Infammation
Heat Shock Factors (HSFs)
HSF-1 monomer and Trimer
Negative feedback
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17. THANKYOU
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