Protein Folding: Flashcards
The more complex a protein is, the _________ likely mutations are to occur
More
l’anémie falciforme, maladie génétique occurs due to:
A to T in the hemogloblin gene
From GAG to GTG → new amino acid, although only one amino acid it leads to misfolded protein → l’anémie falciforme, maladie génétique
Cataractes are related to the misfolding of ____________?
Alpha-Cristalline
What is Alpha-Cristalline?
This is a chaperone protein
needs to be in an oligo form
Role: d’empêcher la précipitation des protéines dénaturées
With age there is a reduced activity of Alpha-Cristalline
What ate Heat Shock Proteins?
Chaperons that will prevent wrong associations between parts of new proteins but instead allows for the correct conformation
Usually prevent hydrophobe regions from aggregating with each other
Its like oil in vinegar: the oil wants to aggregate to stay stable
As such, HSP proteins will prevent these aggregations and allow for proper protein folding
True or False,
Heat Shock Protein associated folding is not an ATP depended process.
FALSE
Do not need ATP to help folding the protein but needs ATP to detach from protein
True of False and explain
App 50 % des protéines sont éliminées à cause de leur
mauvaise conformation
TRUE
It is easier for a cell to make more of the stock and throw away the useless ones than to make perfect stock
What is the Ubiquitine Proteosome System?
It is possible that the protein still is incorrectly folded → as such we use UPS system to degrade them:
Sont marquées pour dégradation par l’ajout d’une étiquette
Ubiquitine
We need a chain of ubiquitin : At least 4 ubiquitines
True or False,
Ubiquitine and the targetted protein will be degraded through the use of a molecular complex called a Proteosome.
FALSE
Les Ubiquitinesont clivées avant de que la protéine ciblée rentre le tube
What missfolding protein is this related to?
Loss of phénylalanine 508 → loss of a chlore channel → less chlore control
Cystic Fibrosis:
What is it that determines whether we are atteint by Huntingtons disease?
Related to séquence poly-Glutamine, dites Poly-Q dans la protéine:
Le nombre de triplet CAG répétés détermine si on est atteint ou pas et l’âge du début de symptômes
What missfolding protein is this related to?
forming of aggregats fibres amyloïdes
Diminution de l’efficacité du repliement et la dégradation de protéines avec l’âge
Related to séquence poly-Glutamine, dites Poly-Q dans la protéine:
Huntington’s Disease:
Explain Maladies causées par des Prions?
Prions: Protéine qui peut se trouver dans deux ou plus
conformations, dont une est autoréplicative
Feedforward system: The misfolded protein can take a neighbor well folded protein and convert it to a misfolded protein and so on
Kuru:
Discovered in a particular group due to their culture (eating the dead)
So this is not a genetic disease.
