Chaperone Mechanism of Grp94: Elucidating ER Protein Quality Control

Description

This lecture delves into the chaperone mechanism of Grp94, an essential ER resident molecular chaperone. It explores the role of ER Hsp90 and Hsp70 in protein homeostasis, client protein activation, and collaboration with cochaperones. The highly conserved Grp94 assists in stabilizing and reactivating client proteins, with ATP-dependent conformational changes. The interaction between Hsp90s and Hsp70s, the function of J-proteins in substrate interactions, and the stimulation of BIP ATP hydrolysis are also discussed. The lecture investigates the collaboration between Grp94 and the BiP chaperone system, the role of ATP binding/hydrolysis in protein refolding, and the importance of a fully functional BiP system in client remodeling. It concludes by examining the reverse mechanism of Grp94/BiP compared to cytosolic chaperones.

Official source

https://mediaspace.epfl.ch/media/0_h4gueynf

About this result

This page is automatically generated and may contain information that is not correct, complete, up-to-date, or relevant to your search query. The same applies to every other page on this website. Please make sure to verify the information with EPFL's official sources.

Related lectures (29)

Related concepts (67)

Chaperone (protein)

In molecular biology, molecular chaperones are proteins that assist the conformational folding or unfolding of large proteins or macromolecular protein complexes. There are a number of classes of molecular chaperones, all of which function to assist large proteins in proper protein folding during or after synthesis, and after partial denaturation. Chaperones are also involved in the translocation of proteins for proteolysis. The first molecular chaperones discovered were a type of assembly chaperones which assist in the assembly of nucleosomes from folded histones and DNA.

Heat shock protein

Heat shock proteins (HSP) are a family of proteins produced by cells in response to exposure to stressful conditions. They were first described in relation to heat shock, but are now known to also be expressed during other stresses including exposure to cold, UV light and during wound healing or tissue remodeling. Many members of this group perform chaperone functions by stabilizing new proteins to ensure correct folding or by helping to refold proteins that were damaged by the cell stress.

ATP synthase

ATP synthase is a protein that catalyzes the formation of the energy storage molecule adenosine triphosphate (ATP) using adenosine diphosphate (ADP) and inorganic phosphate (Pi). ATP synthase is a molecular machine. The overall reaction catalyzed by ATP synthase is: ADP + Pi + 2H+out ATP + H2O + 2H+in ATP synthase lies across a cellular membrane and forms an aperture that protons can cross from areas of high concentration to areas of low concentration, imparting energy for the synthesis of ATP.

Protein folding

Protein folding is the physical process where a protein chain is translated into its native three-dimensional structure, typically a "folded" conformation, by which the protein becomes biologically functional. Via an expeditious and reproducible process, a polypeptide folds into its characteristic three-dimensional structure from a random coil. Each protein exists first as an unfolded polypeptide or random coil after being translated from a sequence of mRNA into a linear chain of amino acids.

Luciferase

Luciferase is a generic term for the class of oxidative enzymes that produce bioluminescence, and is usually distinguished from a photoprotein. The name was first used by Raphaël Dubois who invented the words luciferin and luciferase, for the substrate and enzyme, respectively. Both words are derived from the Latin word lucifer, meaning "lightbearer", which in turn is derived from the Latin words for "light" (lux) and "to bring or carry" (ferre).