PLETHORA-autophagy axis activates organ regeneration through ROS modulation

Area of Science:

• Plant biology
• Cellular stress response
• Molecular mechanisms of regeneration

Background:

• Cellular homeostasis is disrupted by injury, leading to stress at wound sites.
• Autophagy is a conserved pathway for recycling cellular components to maintain homeostasis.

Purpose of the Study:

• To investigate the role of autophagy in plant wound repair and regeneration.
• To understand how plants manage wound-induced cellular stress.

Main Methods:

• Examined transcriptional activation of autophagy-related gene 8 (ATG8) genes.
• Investigated the function of PLETHORA (PLT) transcription factors in regulating ATG8.
• Assessed the impact of disrupting the PLT-ATG8 axis on organelle turnover and reactive oxygen species (ROS) levels.

Main Results:

• Transcriptional activation of ATG8 genes is essential for de novo root regeneration but not callus formation.
• PLT transcription factors activate a subset of ATG8 genes and are critical for this process.
• Disruption of the PLT-ATG8 axis impairs organelle turnover, increases intracellular stress, and leads to ectopic ROS accumulation.

Conclusions:

• The PLT-ATG8 regulatory axis manages wound-induced cellular stress by optimizing ROS levels.
• This pathway promotes stem cell regulator expression, facilitating de novo root regeneration.
• Plants use specific developmental regulators like PLTs to activate conserved pathways for stress management and regeneration.