New Study Reveals Mechanism Guiding De Novo Root Organogenesis in Arabidopsis thaliana
Many differentiated plant organs have an ability to regenerate a new plant after detachment via de novo organogenesis. Recently, researchers from the Chinese Academy of Sciences reported that the WUSCHEL-RELATED HOMEOBOX 11 (WOX11) transcription factor is involved in controlling stem cell fate transition during de novo root organogenesis in the model plant Arabidopsis thaliana.
De novo root organogenesis, the first physiological process occurring during plant regeneration from detached aerial organs, produces adventitious roots to ensure water supply for survival of explants. However, little is known about the molecular mechanism guiding the regeneration of adventitious roots.
The research from the team led by HUANG Hai and XU Lin in Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences developed a simple method to study de novo root organogenesis using B5 medium without added hormones. This method mimics the natural conditions for plant regeneration, which is dependent on endogenous hormones. The team revealed two steps of cell fate transition during adventitious root formation from Arabidopsis leaf explants. Wounding-induced auxin accumulation directly activates WOX11 expression and triggers the first-step cell fate transition from leaf procambium to root founder cells. WOX11 upregulates LATERAL ORGAN BOUNDARIES DOMAIN (LBD) genes, which triggers cell division and the second-step cell fate transition from root founder to root primordium cells. This study provided a cellular and molecular framework of de novo root organogenesis, and suggested that WOX11 might be a key gene that controls the fate transition of stem cells.
This work entitled “WOX11 and 12 Are Involved in the First-Step Cell Fate Transition during de Novo Root Organogenesis in Arabidopsis” has been published online in the Plant Cell on March 18. This work was supported by grants from National Basic Research Program of China (973 Program, 2014CB943500/2012CB910503).
Figure Legend. Cellular and molecular framework of de novo root organogenesis. (Image by Dr. HUANG Hai and Dr. XU Lin's group).