beclin-1

By Michalina Hanzel, PhD

By Christina Towers, PhD

By Jamshed Arslan Pharm.D.

The process of autophagy, or lysosome-mediated degradation of damaged proteins and organelles in the cytosol, is a vital cellular process that acts as a quality control mechanism for proteins and organelles. The misregulation of autophagy can lead to an imbalance of cellular homeostasis and the subsequent development of disease.  Therefore, the study of autophagy is at the forefront of neuroscience and cancer research, among others.

Autophagy is a crucial cellular process that clears the cell of protein aggregates, toxins, and damaged cell products. Accumulation of toxins, damaged cell products and unwanted proteins has been proven to play a role in aging and many forms of disease and cancer.

Autophagy is a crucial intracellular pathway that manages the degradation and recycling of long-lived proteins in the cell. The LC3 (or light chain 3) family is composed of three members, LC3A, LC3B and LC3C. Upon autophagy induction, LC3 is cleaved, causing the release of a C-terminal glycine that is required for phospholipid conjugation.  This process is vital to the formation of the autophagosome, a double membrane structure that delivers proteins to the lysosome during autophagy.

Autophagy is an essential process that maintains cellular homeostasis and carries out lysosome-mediated degradation of unwanted proteins in the cytoplasm.  Because of this regulatory function, autophagy is often examined when looking at disease pathways.  While our immune system initiates the removal of viruses and pathogens through the autophagic pathway, viruses, such as HIV, have developed a way to evade this process through inhibition.  Therefore, developing a reliable way to examine the molecular process of this inhibition and interaction is very desired.  The central autophagy

VPS34, vacuolar protein sorting 34, is the only identified Class III phosphoinositide-3 kinase (PI3K) in mammals and is ubiquitously expressed in all eukaryotic cells. VPS34 is a 100 kDa protein responsible for phosphorylating phosphatidylinositol to produce phosphatidylinositol 3-phosphate (PI3P). PI3P is an important intermediate in the development of the double-membraned autophagosome during autophagy, indicating a role for VPS34 in autophagy initiation. PI3P allows VPS34 to form complexes with ATG14L during the elongation of the autophagosome membrane.

Autophagy is an important cellular process involved in degradation and recycling of cellular macromolecules in response to stress or starvation. Autophagy is carried out in four main phases: phagophore nucleation, autophagosome elongation, docking and fusion with a lysosome, and vesicle breakdown and degradation. ULK1, also known as UNC51-like autophagy activating kinase 1, is a 112 kDa protein with serine-threonine kinase activity. ULK1 is one of two mammalian homologues of the yeast ATG1 kinase, known for its role in autophagy initiation (1).

Autophagy, a protein degradation process through autophagosome-lysosomal pathway, is important for cellular homeostasis and plays a role in many diseases. To help researchers learn more about this process and the products available for its study, Novus Biologicals has released a new Autophagy catalog.