Co-licalization with lysosomes
The Jenny Lab

Department of
Developmental and Molecular Biology at

Albert Einstein

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Science at the Heart of Medicine
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Proper turnover of organelles and proteins is essential for normal cell function during life. Damaged or altered cytosolic proteins are cleared by the proteasome and autophagy. Importantly, autophagy has the additional role of providing nutrients to cells under stress conditions such as starvation, and is thus essential for energy balance. There is a strong correlation between lifespan extension, age related diseases and levels of autophagy. Not surprisingly, autophagy declines with age and is associated with the accumulation of altered, defective components in all model organisms examined, including mice and Drosophila, and experimental reduction of autophagy in animal models leads to reduced organ function and a shortened life span.

Although Macroautophagy (MA) can selectively degrade organelles or aggregate proteins, selective degradation of single proteins has only been described for Chaperone Mediated Autophagy (CMA) and endosomal Microautophagy (eMI). These two autophagic pathways, described to date only in mammals, are specific for proteins containing a KFERQ-related targeting motif. In collaboration with the Cuervo lab in our department, we have identified an eMI-like pathway in Drosophila melanogaster using a KFERQ-tagged fluorescent biosensor. We are curretly using the power of genetics to identify kinases and phosphatases that may regulate this pathway.

Reporter puncta form upon starvation

CMA like dots induced by starvation

KFERQ-reporter puncta form in the larval fat body upon prolonged starvation. Nuclei are in blue in composite.