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Cancer Research Posters

Acute Myeloid Leukemia, Melanoma & Mitochondrial Dynamics Posters


Apoptosis Webinar

"A question of Life or Death" - differentiating between healthy and apoptotic cells

Autophagy Overview

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.

Upstream Events

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 (CD107a) & Lamp2 (CD107b)) 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:


Upstream Events

  • Chu, C.T. et al. (2004) Oxidative neuronal injury. The dark side of ERK1/2.
    Eur. J. Biochem. 271: 2060–2066.
  • Flotte, T.J. et al. (1983) Dendritic cell and macrophage staining by monoclonal antibodies in tissue sections and epidermal sheets.
    Am. J. Pathol. 111:112-124.
  • Gozuacik, D. and Kimchi, A (2004) Autophagy as a cell death and tumor suppressor mechanism.
    Oncogene. 23: 2891-2906.
  • Ho, M.K. and Springer, T.A. (1983) Tissue distribution, structural characterization and biosynthesis of Mac-3, a macrophage surface glycoprotein exhibiting molecular weight heterogeneity.
    J. Biol. Chem. 258:636-642.
  • Liang, X.H. et al. (1998) Protection against fatal Sindbis virus encephalitis by Beclin, a novel Bcl-2-interacting protein.
    J. Virol. 72: 8586-8596.
  • Liang, X.H. et al. (1999) Induction of autophagy and inhibition of tumorigenesis by beclin 1.
    Nature. 402: 672-676.
  • Nishimoto, S. and Nishida, E. (2006) MAPK signalling: ERK5 versus ERK1/2.
    EMBO Rep. 7: 782-6.
  • Raman, M. et al. (2007) Differential regulation and properties of MAPKs.
    Oncogene. 26:3100-12.
  • Reif, K. et al. (1993) Divergent regulation of phosphatidylinositol 3-Kinase P85 alpha and P85 beta isoforms upon T cell activation.
    J. Biol. Chem. 278: 10780-10788.
  • Semba, S. et al. (2002) Down-regulation of PIK3CG, a catalytic subunit of phosphatidylinositol 3-OH kinase, by CpG hypermethylation in human colorectal carcinoma.
    Clin. Cancer Res. 8:3824-3831.
  • Serajee, F.J. et al. (2003) Association of INPP1, PIK3CG, and TSC2 gene variants with autistic disorder: implications for phosphatidylinositol signalling in autism.
    J. Med. Genet. 40:119.
  • Shamji, A.F. et al. (2003) Integration of growth factor and nutrient signaling: Implications for cancer biology.
    Mol. Cell 12: 271-280.
  • Springer, T.A. (1981) Monoclonal antibody analysis of complex biological systems. Combination of cell hybridization and immunoadsorbents in a novel cascade procedure and its application to the macrophage cell surface
    J. Biol. Chem. 256:3833-3839.
  • Stern, D.F. (2004) More than a marker… Phosphorylated Akt in prostate carcinoma.
    Clin Cancer Res. 10: 6407-10.
  • Tatin, F. (2010) Sodium fluoride induces podosome formation in endothelial cells.
    Biol Cell. May 26. [Epub ahead of print]
  • Turjanski, A. et al. (2007) MAP kinases and the control of nuclear events.
    Oncogene. 26:3240-53.
  • Woodfield, R. et al. (2001) The p85 subunit of phosphoinositide 3-kinase is associated with beta-catenin in the cadherin-based adhesion complex.
    Biochem. J. 360: 335 - 344.

Autophagy Pathway

  • Espinosa, I. et al. (2009) Coordinate expression of colony-stimulating factor-1 and colony-stimulating factor-1-related proteins is associated with poor prognosis in gynecological and nongynecological leiomyosarcoma.
    Am J Pathol. 174: 2347-2356.
  • Iwata, A. et al. (2005). HDAC6 and microtubules are required for autophagic degradation of aggregated Huntington.
    J. Biol. Chem. 280: 40282-40292
  • Kopitar-Jerala, N. et al. (2001) Anti-Cathepsin L monoclonal antibodies that distinguish cathepsin L from cathepsin V. Biol.
    Chem. 382: 867-870.
  • Martin, S.L. et al. (2010) Association of airway cathepsin B and S with inflammation in cystic fibrosis.
    Pediatr Pulmonol. Jul 14.[Epub ahead of print]