Autophagic degradation

Sakaida, S., Kyle, M. and Farber, J.L. (1990). Autophagic degradation of protein generates a pool of ferric iron required for the killing of cultured hepatocytes by an oxidative stress. Mol. Pharmacol. 37, 435-442. 

On the basis of the pathway of heterophagy (Fig. 1-8), make a proposal for the pathway of autophagic degradation of a mitochondrion. 

Iwata A et al (2005) HDAC6 and microtubules are required for autophagic degradation of aggregated huntingtin. J Biol Chem 280(48) 40282-40292... 

Figure 1-15 shows the scheme for autophagic degradation of a mitochondrion. Note that once the phagosome has been formed, the process of digestion, etc. is the same as for heterophagy. 

Our recent studies have shown that ragged-red fibers in muscle biopsies in various neuromuscular disorders contain accumulated a-syn and parkin (Plate 7.5b-d) [128]. We propose that abnormal mitochondria within the ragged-red fibers are destined for autophagic degradation, and parkin is recruited to facilitate their clearance, as has been reported in other systems [125, 131]. 

Bjorkoy G, Lamark T, Pankiv S et al (2009) Monitoring autophagic degradation of p62/ SQSTMl. Methods Enzymol 452 181-197... 

Seglen PO, Gordon PB, Poli A. Amino acid inhibition of autophagic/lysosomal pathway of protein degradation in isolated rat hepatocytes. Biochim Biophys Acta 1980 630 103-118. 

Seglen, P.O. Gordon, P.B. (1984). Amino acid control of autophagic sequestration and protein degradation in isolated rat hepatocytes. J. Cell. Biol. 99,435-444. 

A portion of the cytoplasm or an entire organelle (e.g., peroxisome) can be enveloped in a flattened membrane and eventually incorporated into a double-membraned autophagic vesicle. Fusion of the outer vesicle membrane with the lysosome delivers the enveloped contents to the interior of the lysosome for degradation. 

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