Tag: Proteostasis

Protein carbonylation is an important oxidative post-translational modification associated with reactive oxygen species, oxidative stress, protein damage, aging, mitochondrial dysfunction, inflammation, and disease. Learn how carbonylated proteins form, affect cellular function, and are detected.

Protein pyroglutamate formation is an N-terminal post-translational modification that affects protein stability, peptide maturation, degradation, aggregation, and biological activity.

Protein AMPylation is a dynamic post-translational modification in which AMP is covalently attached to proteins. Discover its mechanisms, enzymes, substrates, biological functions, and importance in cellular regulation and bacterial pathogenesis.

Protein deamidation is a chemical modification in which asparagine or glutamine residues are converted into acidic amino acids. Learn how deamidation affects protein structure, stability, aging, proteostasis, disease, and therapeutic proteins.

Protein folding is the process by which newly synthesized proteins acquire their functional three-dimensional structures. Discover how folding occurs, what influences it, and how cells manage misfolded proteins.

ATF6 is an ER stress‑responsive transcription factor that enhances protein‑folding capacity and strengthens ER‑associated degradation. After trafficking to the Golgi and undergoing regulated proteolysis, ATF6 activates genes that restore ER proteostasis during unfolded protein accumulation.

ER stress arises when misfolded proteins accumulate in the endoplasmic reticulum, overwhelming its folding capacity. Through IRE1, PERK and ATF6 signalling, the unfolded protein response restores proteostasis, reduces protein load and protects cells from stress‑induced damage.

Programmed cell death (PCD) is a regulated biological process that eliminates damaged or unnecessary cells through apoptosis, autophagic cell death and regulated necrosis. By maintaining tissue homeostasis and supporting stress adaptation, PCD is essential for development and long‑term organismal health.

Protein misfolding occurs when proteins fail to achieve or maintain their correct three-dimensional structures. Explore its causes, cellular consequences, quality-control mechanisms, and connection to disease.

Protein homeostasis is the process by which cells maintain a balance between protein synthesis and degradation. This balance is essential for protein quality, cellular function, growth, adaptation, and survival.

ERAD is a central ER quality‑control pathway that recognises misfolded proteins, retrotranslocates them to the cytosol, ubiquitinates them and directs them to the proteasome. By preventing proteotoxic accumulation, ERAD preserves ER homeostasis and supports cellular proteostasis.

PERK is a central ER stress sensor that phosphorylates eIF2α, reduces protein synthesis and activates ATF4‑dependent transcription. Through adaptive and apoptotic signalling, PERK coordinates unfolded protein response pathways that restore proteostasis or eliminate irreparably damaged cells.

IRE1 is the most conserved ER stress sensor, activating XBP1 splicing and RIDD to restore proteostasis. Through its kinase and RNase activities, IRE1 detects misfolded proteins, initiates adaptive signalling and coordinates the unfolded protein response during ER stress.

The proteostasis network is an integrated system of chaperones, degradation pathways and organelle‑specific quality‑control mechanisms that maintains protein folding, stability and function. By coordinating refolding, repair and degradation, cells prevent proteotoxic stress and preserve homeostasis.

The unfolded protein response (UPR) is a conserved ER stress pathway that detects misfolded proteins and restores proteostasis. Through IRE1, PERK and ATF6 signalling, cells expand folding capacity, reduce protein load and maintain homeostasis under conditions of ER stress.