Plant Cell Reports

, Volume 37, Issue 4, pp 653–664 | Cite as

Autophagy-related (ATG) 11, ATG9 and the phosphatidylinositol 3-kinase control ATG2-mediated formation of autophagosomes in Arabidopsis

  • Sangwoo Kang
  • Kwang Deok Shin
  • Jeong Hun Kim
  • Taijoon Chung
Original Article


Key message

Using quantitative assays for autophagy, we analyzed 4 classes of atg mutants, discovered new atg2 phenotypes and ATG gene interactions, and proposed a model of autophagosome formation in plants.


Plant and other eukaryotic cells use autophagy to target cytoplasmic constituents for degradation in the vacuole. Autophagy is regulated and executed by a conserved set of proteins called autophagy-related (ATG). In Arabidopsis, several groups of ATG proteins have been characterized using genetic approaches. However, the genetic interactions between ATG genes have not been established and the relationship between different ATG groups in plants remains unclear. Here we analyzed atg2, atg7, atg9, and atg11 mutants and their double mutants at the physiological, biochemical, and subcellular levels. Involvement of phosphatidylinositol 3-kinase (PI3K) in autophagy was also tested using wortmannin, a PI3K inhibitor. Our mutant analysis using autophagy markers showed that atg7 and atg2 phenotypes are more severe than those of atg11 and atg9. Unlike other mutants, atg2 cells accumulated several autophagic vesicles that could not be delivered to the vacuole. Analysis of atg double mutants, combined with wortmannin treatment, indicated that ATG11, PI3K, and ATG9 act upstream of ATG2. Our data support a model in which plant ATG1 and PI3K complexes play a role in the initiation of autophagy, whereas ATG2 is involved in a later step during the biogenesis of autophagic vesicles.


Autophagosome Phagophore GFP-ATG8 Phosphatidylethanolamine atg18a 



We thank Dr. Richard Vierstra for providing ATG8 antiserum. This work is supported by grants NRF-2014R1A1A1A05003740 and “Cooperative Research Program for Agriculture Science & Technology Development (PJ01110801), Rural Development Administration, Korea” to T.C.

Compliance with ethical standards

Conflict of interest

The authors have no conflict of interest.

Supplementary material

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Supplementary material 1 (DOCX 28 KB)
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Supplementary material 2 (EPS 9011 KB)
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Supplementary material 3 (EPS 8909 KB)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Biological SciencesPusan National UniversityBusanRepublic of Korea
  2. 2.Institute of Systems BiologyPusan National UniversityBusanRepublic of Korea

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