Tag: Autophagy

Branched-chain amino acids (BCAAs) are the essential amino acids leucine, isoleucine, and valine. They play important roles in protein synthesis, muscle metabolism, energy production, nutrient sensing, mTOR signaling, nitrogen metabolism, exercise physiology, and metabolic health.

Protein ubiquitination is a fundamental post-translational modification that regulates protein degradation, cellular signaling, DNA repair, autophagy, protein trafficking and cellular homeostasis.

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.

Autophagy is the cell’s built‑in recycling system, removing damaged proteins and organelles to maintain health and survive stress. This article explains how autophagy works, its role in immunity, aging, and disease, and why it is essential for cellular balance.

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.

Cellular stress responses are adaptive defence mechanisms that protect cells from environmental, metabolic and proteotoxic stress. By activating heat‑shock proteins, unfolded protein responses, antioxidant pathways and autophagy, cells restore homeostasis and maintain functional integrity under adverse conditions.

Protein quality control (PQC) is a cellular surveillance system that preserves proteome integrity by monitoring protein folding, repairing misfolded proteins and eliminating damaged or aggregated species. Through coordinated action of chaperones, the ubiquitin–proteasome system and autophagy, PQC protects cells from proteotoxic stress and maintains homeostasis.

The TRIM family is a large group of single‑chain RING finger ubiquitin ligases that regulate innate immunity, antiviral defence, autophagy, transcription and protein quality control. Defined by their tripartite motif—RING, B‑box and coiled‑coil domains—TRIM proteins use diverse C‑terminal regions to achieve precise substrate specificity. Their roles in immunity, development and cancer make them key regulators of cellular homeostasis.

K63‑linked ubiquitination is a non‑degradative signalling modification that assembles scaffold‑like ubiquitin chains regulating DNA repair, NF‑κB activation, receptor endocytosis and autophagy. Built by UBE2N/UBE2V1 and specialised E3 ligases, K63 chains coordinate dynamic cellular responses without targeting proteins for proteasomal degradation.

Premature ageing describes the accelerated decline of cellular and physiological functions caused by genomic instability, telomere attrition, mitochondrial dysfunction and chronic inflammation. These processes activate ageing pathways earlier than expected, leading to early onset of tissue deterioration, reduced homeostasis and increased vulnerability to age‑related diseases.

Ageing is a gradual biological process driven by genomic instability, telomere shortening, mitochondrial dysfunction and cellular senescence. These changes reduce physiological resilience, impair tissue repair and increase susceptibility to chronic disease. Understanding the mechanisms of ageing provides insight into longevity, healthspan and the development of age‑related disorders.

Nutrient deprivation creates metabolic stress that suppresses mTOR, activates AMPK and induces autophagy. These pathways help cells conserve energy, recycle intracellular components and maintain homeostasis during starvation or limited nutrient availability. Prolonged nutrient deprivation influences gene expression, stress signalling and survival mechanisms across diverse cell types.

Hydrolytic enzymes catalyse the breakdown of macromolecules by adding water to chemical bonds. Found in lysosomes, digestive organs and immune cells, they degrade proteins, nucleic acids, lipids and carbohydrates. Their activity maintains cellular homeostasis, supports nutrient acquisition and protects against pathogens, while dysregulation contributes to metabolic and degenerative diseases.