Mechanisms of Selective Autophagy

Abstract

Selective autophagy contributes to intracellular homeostasis by mediating the degradation of cytoplasmic material such as aggregated proteins, damaged or over-abundant organelles, and invading pathogens. The molecular machinery for selective autophagy must ensure efficient recognition and sequestration of the cargo within autophagosomes. Cargo specificity can be mediated by autophagic cargo receptors that specifically bind the cargo material and the autophagosomal membrane. Here we review the recent insights into the mechanisms that enable cargo receptors to confer selectivity and exclusivity to the autophagic process. We also discuss their different roles during starvation-induced and selective autophagy. We propose to classify autophagic events into cargo-independent and cargo-induced autophagosome formation events.

KIF1A/UNC-104 Transports ATG-9 to Regulate Neurodevelopment and Autophagy at Synapses

“…However, the autophagy pathway can also selectively degrade specific organelles or target proteins in certain contexts. This process, known as selective autophagy, is dependent on the adaptor molecule Atg11, which interacts with cargo receptors to link specific protein targets to the autophagosome precursor membrane (Farre et al, 2013; He et al, 2006; Mao et al, 2013; Yorimitsu and Klionsky, 2005; Zaffagnini and Martens, 2016). Additional selective autophagy adaptors include the nematode-specific epg-2 (Tian et al, 2010) and the C. elegans homolog of p62, sqst-1 (Table S1) (Lamark et al, 2009; Lin et al, 2013).…”

Selective autophagy limits cauliflower mosaic virus infection by NBR1-mediated targeting of viral capsid protein and particles

“…Ample evidence now indicates that autophagy, initially recognized as a mainly bulk catabolic process, is able specifically to target and degrade a multitude of cellular structures ranging from individual and aggregated proteins to entire organelles and invading microbes (5,6). Selectivity is provided by a growing number of autophagic adaptor or receptor proteins identified in eukaryotic organisms that recruit the cargo to the developing autophagosome through interaction with membrane-associated ATG8/LC3 proteins (7,8). Several mammalian autophagy receptors have been implicated in the targeting of intracellular bacterial and viral pathogens in a process called "xenophagy" (8)(9)(10).…”

“…Selectivity is provided by a growing number of autophagic adaptor or receptor proteins identified in eukaryotic organisms that recruit the cargo to the developing autophagosome through interaction with membrane-associated ATG8/LC3 proteins (7,8). Several mammalian autophagy receptors have been implicated in the targeting of intracellular bacterial and viral pathogens in a process called "xenophagy" (8)(9)(10). For instance, the cargo receptor p62 (SQSTM1) was shown to bind directly to and mediate autophagic clearance of different viral capsid proteins (11)(12)(13).…”

Autophagy in Plant Pathogenic Fungi

“…These processes include the CVT pathway (which is only found in S. cerevisiae), pexophagy (which targets peroxisomes), mitophagy (the specific elimination of mitochondria), nucleophagy (which targets the nucleus), reticulophagy (which mediates the turnover of the endoplasmic reticulum), and ribophagy (the specific elimination of ribosomes) [83]. Here, we provide a brief introduction to the mechanisms that have been identified and the development of selective autophagy in plant pathogenic fungi.…”