"A question of Life or Death” - differentiating between healthy and apoptotic cells
Dr Judith Langenick (Product Manager at Bio-Rad)
The evolutionary conserved autophagy process is under renewed research interest with the discovery of the ATG gene products and the link between autophagy and aging as well as human diseases. A suggested role for autophagy in programmed cell death and cell cycle progression along with further elucidation of the autophagy mechanisms and their regulation are also under investigation.
We offer a selection of autophagy related antibodies and cathepsin detection kits, all performance guaranteed in many popular applications, for the study of upstream events, autophagy pathways and lysosome detection.
Cellular stress conditions initiate upstream events through the MAPK/Erk1/2, PI3K/AKT and mammalian target of rapamycin (mTOR) pathways with mTORC complexes leading to the autophagy mechanisms macroautophagy, microautophagy and chaperone-mediated autophagy (CMA) in eukaryotic cells.
Macroautophagy is the most studied pathway involving the cellular degradation of cytoplasmic proteins, bulk cytoplasm, dysfunctional organelles and intracellular pathogens (innate immunity / cell defense mechanism). This process involves the formation of a phagophore which develops into a transport vesicle called the autophagosome containing the cytoplasmic constituents or organelles.
The autophagy machinery, including the phagophore assembly site / pre-autophagosomal structure (PAS), and its regulation involves more than 30 autophagy related genes (ATG Proteins) including Beclin 1, Activating molecule in beclin-1-regulated autophagy (AMBRA1), Damage-regulated autophagy modulator (DRAM), lysosome-associated membrane proteins (Lamp1 & 2 (CD107a & b) and Microtubule-associated proteins 1A/1B light chains 3A/B (MAP1LC3A/B).
Autophagosome Marker – LC3 Antibody
Microtubule-associated proteins 1A/1B light chains 3A/LC3A and 3B/LC3B (MAP1LC3A/B) are ubiquitin-like proteins used as reliable markers for monitoring autophagy. MAP1LC3A/B is commonly further abbreviated to LC3.
A popular method for detecting autophagy uses antibodies specific to LC3 to identify LC3-positive structures such as autophagosomes. Since LC3 is the only protein identified on the inner and outer membranes of autophagosomes, MAP1LC3A/B antibodies provide a quick detection method.
Click here to learn more about our LC3 antibody, which shows superior Western blotting results.
Lysosome Detection – Cathepsin Antibodies and Detection Kits
The autophagosome fuses to a lysosome forming an autolysosome where enzymes such as cathepsins and permeases hydrolyze and degrade the cargo for its release back into the cytoplasm for recycling.
Our Magic Red™ Cathepsin B, K and L Detection Kits are suitable for detection of lysosomes:
Active cathepsin analysis in whole, living cells
Substrate based assay
Fluorescence microscopy or plate reader
We also offer a range of Cathepsin Antibodies; further details about our Cathepsin Detection Kits and antibodies are available here. Our cathepsin kits are part of our apoptosis detection kits range.
Future detailed understanding of autophagy mechanisms and their role in human disease and innate and adaptive immunity is needed before potential therapeutic intervention can be developed.
Autophagy is thought to be closely linked to apoptosis; view the other sections in our quality apoptosis antibodies and kits product range:
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Magic Red™Cathepsin Kit is a trademark of Immunochemistry Technologies Inc. USA.