The Role of Autophagy in Mammalian Development: Cell Makeover Rather than Cell Death

Dulbecco Telethon Institute at the Department of Biology, University of Rome Tor Vergata, 00133 Rome, Italy.
Developmental Cell (Impact Factor: 9.71). 10/2008; 15(3):344-57. DOI: 10.1016/j.devcel.2008.08.012
Source: PubMed


Autophagy is important for the degradation of bulk cytoplasm, long-lived proteins, and entire organelles. In lower eukaryotes, autophagy functions as a cell death mechanism or as a stress response during development. However, autophagy's significance in vertebrate development, and the role (if any) of vertebrate-specific factors in its regulation, remains unexplained. Through careful analysis of the current autophagy gene mutant mouse models, we propose that in mammals, autophagy may be involved in specific cytosolic rearrangements needed for proliferation, death, and differentiation during embryogenesis and postnatal development. Thus, autophagy is a process of cytosolic "renovation," crucial in cell fate decisions.

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Available from: Francesco Cecconi, Dec 24, 2014
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    • "In particular, in mammals, autophagy may be involved in specific cytosolic rearrangements needed for proliferation and differentiation during embryogenesis and postnatal development. Thus, autophagy is a process of cytosolic " reno‐ vation " , crucial for cell fate decisions [10]. However, in both invertebrate and vertebrate organisms, it is generally thought that autophagy plays an essential dual role both in the adaptation to stress and in the starvation occurring during morphogenesis, as well as in cell elimination in concert with the apoptotic machinery. "

    Full-text · Chapter · Oct 2015
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    • "The autophagy-lysosomal pathway (ALP) is an evolutionarily conserved catabolic process by which the cell removes and recycles complexes, protein aggregates and damaged organelles [24]. Often observed as a mechanism to address starvation and reduce energy output, autophagy can also contribute to cellular differentiation, growth control, defense from xenobiotics, as well as general housekeeping and maintenance [25]. Thus, autophagy is generally thought of as a survival mechanism. "
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    • "Additionally, it has been observed that mTOR inhibition induces a variety of processes, including macroautophagy (hereafter referred to as autophagy) (Loewith et al., 2002). This evolutionary conserved process is normally responsible for protein turnover and the elimination of damaged organelles and cytoplasmic components in order to maintain homeostasis in the cell (Cecconi and Levine, 2008). Under pathological conditions such as cancer, autophagy is considered to serve as a pro-survival mechanism (Chen and Karantza-Wadsworth, 2009). "
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