Cathepsin D mediates apoptosis during anuran tail regression

International Conference on Histochemistry & Cell Biology

September 14-15, 2016 Phoenix, USA

Pravati Kumari Mahapatra

Utkal University, India

Posters & Accepted Abstracts: J Cytol Histol

Abstract :

Apoptosis is a genetically regulated form of cell death which has a role in embryogenesis, ageing, and many diseases. Many existing treatments like anti-cancer treatments act through apoptosis. New treatments are also being developed to modify apoptosis and can be used to manage common diseases. Anuran tail regression is a prominent example of programmed cell death mediated by apoptosis. Anuran tail thus acts as an efficient model to study apoptosis, since tail resorption during anuran metamorphosis is exclusively mediated by apoptosis. The tail undergoes complete resorption during metamorphosis to adapt to terrestrial mode of life in the adult phase of life. Lysosomal enzymes play pivotal role in degrading the tail tissues where they mainly degrade the cellular debris taken up by macrophages after initial death of cells under the influence of thyroid hormone. However, recent studies on tropical anurans have showed that lysosomal cathepsins especially, cathepsin D acts much earlier in the cell death process rather than only clearing cellular debris. Immunohistochemical localization of cathepsin D showed that it localized to apoptotic epidermal and muscle cells. Besides, cathepsin D also localized to degenerating blood cells, spinal cord and notochordal cells. Melanocytes, a source of lysosomal enzymes, were found in large numbers near the degrading tail tissues. Thus, cathepsin D seems to cause the initial cell death of the tail tissues which is followed by clearing of the cellular debris later on by melanocytes. Further studies should focus on the downstream effectors activated by cathepsin D which cause the initial death of the tail tissues and the exact role of melanocytes in causing degradation of tail tissues.

Biography :

Email: mahap_pk@yahoo.com