LC3

By Christina Towers, PhD.

The neurodegenerative disorder, Alzheimer's disease, is responsible for 60 to 80% of all dementia cases.¹   Neurodegeneration occurs in response to the accumulation of amyloid-β plaques and neurofibrillary tangles composed of hyperphosphorylated tau.

Autophagy is an essential process that cells utilize to degrade and recycle damaged material and fuel metabolism, especially under stress.  The process is evolutionarily conserved and complex, relying on over 20 key proteins. Induction of autophagy is mediated by the formation of the ULK and BECLIN complexes, the latter of which includes BH3-containing proteins and AMBRA1, resulting in the formation of a double membrane phagophore structure.

Cell death/recycling pathways such as apoptosis, necroptosis, and autophagy are an integral part of the growth, development, homeostasis as well as the pathophysiology in the life of living organisms. These signaling pathways are highly regulated and some of their key regulatory targets are discussed below.

Apoptosis

Apoptosis, programmed cell death, is primarily characterized by the activation of caspases which further regulate the mass cleavage of proteins and DNA. Some of major the proteins responsible for various apoptotic events are:

Apoptosis is a form of programmed cell death which is mediated by cysteine proteases called caspases. It is an essential phenomenon in the maintenance of homeostasis and growth of tissues, and it also plays a critical role in immune response. The cytomorphological alterations and the key features of apoptosis are listed below:

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.

TRIF, also known as toll like receptor adaptor molecule 1 or TICAM1, is known for its role in invading foreign pathogens as part of our innate immune response. TRIF/TICAM1 is a TIR-domain adaptor protein (toll/interleukin-1 receptor) that interacts with the Toll-like receptors (TLRs) through intracellular signaling and recognition of its TIR site.

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

Novus Biologicals' antibodies are the gold standard to monitor autophagy and detect LC3 expression. The recently published Guidelines for the Use and Interpretation of Assays for Monitoring Autophagy (3rd Edition) comprehensively details methods to monitor autophagy in cell or tissue samples. Importantly, these guidelines also provide key considerations for data interpretation and tips to creating better western blot data.