Week 6: Cellular Degradation and Recycling | The Pennsylvania State University

University:
The Pennsylvania State University
Course:
BIOL 230W | Cellular Biology
Academic year:

2023
Views:

255

Pages:

1
Author:

Sarah Landeck

BIOL 230W - Week 6 Cellular Degradation and Recycling — Proteasome: collection of proteins (proteinaceous) that degrades proteins —> lysosomes (membrane-bound) also degrade proteins, fuse with proteasome — If misfolded proteins are not broken down, they aggregate and cause disease —> same w organelles- damaged mitochondria produce dangerous byproducts — Processes that cause correct folding in ER = glycosylation (addition of sugars), chaperone proteins, and disul de bonds (covalent bonds) Cellular Degradation and Recycling pt 2 — If proteins are incorrectly folded and are unable to be refolded, they enter ERAD (endoplasmic reticulum associated degradation) —> in ERAD, protein is exported, ubiquitinated, and degraded by proteasome Cellular Degradation and Recycling pt 3 — BiP binds both to misfolded proteins, as well as the membrane. Membrane-bound BiP regulates the unfolded protein response by turning it o —> UPR activates transcription factors (speci cally activators, bind enhancers) ff fi fi — miRNA degrades mRNA which decreases protein loads