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Beyond Autophagy: ATG9A as an Emerging Membrane Repair Factor

  • Maribel Lara Corona,   
  • Aurore Claude-Taupin *

Received: 08 Jul 2026 | Revised: 18 Aug 2026 | Accepted: 19 Aug 2026 | Published: 27 Aug 2026

Abstract

Membrane damage occurs in all cell types, triggered by environmental cues, pathogens or intrinsic cellular processes. To survive, cells have evolved various mechanisms to repair their membranes. Among these, the autophagic protein ATG9A, initially described as a key factor in autophagy initiation, is now known to participate in multiple stages of autophagy, including phagophore expansion and closure. Moreover, ATG9A has recently been uncovered as playing a crucial role in both plasma membrane and lysosomal membrane repair. In this perspective article, we briefly overview the novel functions of ATG9A and discuss key unanswered questions, including the mechanisms by which ATG9A-containing vesicles promote repair, which may depend on the size and nature of the membrane damage.

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Corona, M. L.; Claude-Taupin, A. Beyond Autophagy: ATG9A as an Emerging Membrane Repair Factor. Ubiquitylation & Atg8ylation 2026, 1 (1), 6.
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