Molecular Biology Reports

, Volume 33, Issue 4, pp 273–278 | Cite as

Identification and characterization of two rice autophagy associated genes, OsAtg8 and OsAtg4

  • Wei Su
  • Haijie Ma
  • Chao Liu
  • Jiaxue Wu
  • Jinshui Yang
Original Paper


Autophagy is an intracellular process for vacuolar degradation of cytoplasmic components. The molecular machinery responsible for yeast and mammalian autophagy has begun to be elucidated at the cellular level. A genome-wide search revealed significant conservation among autophagy genes in yeast and Arabidopsis. Up till now, however, there is no report about rice autophagy associated genes. Here we cloned OsAtg8 and OsAtg4 from Oryza sativa and detected their expression patterns in various tissues. Immunoblotting analysis showed that carboxyl terminus of OsAtg8 can be cleaved in yeast cell. Mutation analysis revealed that the conserved Gly117 residue of OsAtg8 was essential for its characteristic C-terminal cleavage as similar to that found in mammalian and yeast Atg8. We further proved that OsAtg8 interacted with OsAtg4, and this interaction was not affected by the conserved Gly117 mutation. Our results demonstrate that Atg8 conjugation pathway is conserved in rice and may play important roles in rice autophagy.


Autophagy Cleavage Interaction OsAtg8 OsAtg4 



This work was supported by the National Natural Science Foundation of China (Grant No. 30370136).


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Wei Su
    • 1
  • Haijie Ma
    • 1
  • Chao Liu
    • 1
  • Jiaxue Wu
    • 1
  • Jinshui Yang
    • 1
  1. 1.Institute of Genetics, State Key Laboratory of Genetic Engineering, School of Life SciencesFudan UniversityShanghaiChina

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