Good morning. My name is Carmine Settembre.
I'm a group leader at the Telethon Institute of Genetics and Medicine in Naples,
Italy, and also associate professor of
medical genetics at the University of Naples Federico II.
Today, I'm going to talk to you about evidences suggesting that
autophagy dysfnction is one of
the main pathogenic mechanism in lysosomal storage disorders.
So the lysosome is the main catabolic organelle of the cells because it's
able to digest virtually any biological substrates within its lumen.
This digestion is possible thanks to the presence of several lysosomal hydrolases,
which are enzymes that are able to digest virtually any biological substrates,
in a more simple units,
within the lumen of the lysosome.
Cellular substrates are delivered to the lysosome mainly through independent pathway.
Extracellular substrates are delivered to the lysosome via endocytosis,
while intracellular substrates are delivered to the lysosome via autophagy.
The process of autophagy starts with
the biogenesis of double membrane vesicles known as autophagosome.
This double membrane vesicle recognize
intracellular material that needs to be degraded by lysosome.
So then this material is basically sequestered within this double membrane vesicles,
and then delivered to the lysosome upon autophagosome lysosome fusion.
Once this material is delivered within the lysosome,
lysosome hydrolases digest this material in more simple units
such as amino acids from proteins or fatty acids from complex lipids and so on,
and then this digested material is recycled
back within the cytoplasm and then can be reused by the cells,
either to generate energy during period of cell fusion or as
a building block for the biosynthesis of new complex molecules.