Week 2 Flashcards
What do heat shock protiens do
Serve to protect cells from diverse phsyical and chemical insults
Who discovered heat shock response
Ferruccio Ritossa
What happened in the heat shock discovery
Inccaubator was turned up and chromatin puffs form heat induced activation of gene transcrption localized in that specific regions of the cchromosomes
What temperature are heat shock protiens triggered by
Just a few degrees
What are some examples of changes in cell morphology and organization
Remodelling cytoskelton,
fragmentation and disassemble of the golgi and ER, swelling of the nucleoli
What happens in the fibroblasts of a chinese hamster that is treated with hyperthermia
Disruption of the fine structure of the actin filaments but stabilization of the cell cortex (MORE ROUNDED)
What are the 7 classes of proteins for cells to cope with stress
Chaperons
DNA/RNA repair
Metabolic enzymes
Regulatory proteins
Proteolytic system
Transport and detoxification
Cell organization
What are chaperons
Specific proteins that interact with, stabilize or help other protiens to acquire its functionally active conformation without being present in its final structure
What do RNA and DNA enzymes
Necessary to repair DNA damage and processing failures that occur during stress
What are metabolic enzymes
Needed to reorganize and stabilize the energy supply of the cell
What are regulatory protiens
Transcrption factors or kinases needed to further initiate stress response pathways or to inhibit expression cascafes
What is the proteolytic stystem enzymes
Needed to clear misfolded and irreversibly aggregated protiens from the cell
What are cell organization proteins
Required in sustaining cellular structures such as the cytoskeleton
What are transport and detoxifying proteins for
needed to maintain or restore membrane stability and function
What can detect up-regulation of heat shock protein
Western blot technique
What else is important for protein folding pathway
Chaperone HSPS like HSP70
What is the oil drop model
Some proteins are capable of self-assembly into a single stable conformation hydrophobic inside hydrophilic outside
Where do chaperones bind
Hydrophobic patches to prevent misfolding
Do chaperons determine by the three dimensional state
NO amino acid sequences does chaperons just helps them get there
What are the five chaperone families
Hsp100
Hsp90
Hsp70
Hsp 60
sHsps
What chaperone family is energy independent
sHSPs
What are the two general families of chaperones
Molecular chaperones and Chaperonins
What are molecular chaperones
Proteins that bind and stablize unfolded proteins, and facilitate their folding through exposed peptide sequences of hydrophobic amino acids prevent them from aggregating
What are chaperonins
Ring shaped chaperons that form small folding chambers that encapsulate non native protiens in an ATP dependent manner