Transcription factor NF‐YB21 positively regulate the root growth in Populus (New Phytol)

Nuclear factor Y (NF-Y) proteins are heterotrimeric transcription factors made up of A, B and C subunits that exist in higher eukaryotes. Previous work has implicated NF-Ys in root growth. Recently, Zhou et al. isolated a root-specific NF-Y family transcription factor in Populus designated as PdNF-YB21. Overexpression or knockout of PdNF-YB21 results in enhanced or reduced root growth, xylem lignification, and drought resistance respectively. Moreover, PdNF-YB21 interacts with the transcription factor PdFUS3, which activates the promoter of the key ABA synthesis gene PdNCED3. ABA promotes IAA transport in root tips, which ultimately increases root growth and drought resistance. This study revealed a functional module, NF‐YB21‐FUS3‐NCED3, in poplar root growth in response to water-deficit, and also shows how ABA synthesis in Populus influences auxin transport.(Summary by Nanxun Qin) New Phytol.  10.1111/nph.16524