Ubiquitin Ligases in Plants

Plants evolved to use myriad ubiquitin ligases to regulate their physiological functions. Recent studies on the plant hormone auxin have unveiled a novel paradigm of signal transduction, in which ubiquitin ligases function as hormone receptors. Perceived by the F-box protein subunit of the SCF-TIR1 ubiquitin ligase, auxin directly promotes the recruitment of a family of transcriptional repressors for ubiquitination, thereby activating extensive transcriptional programs.

Our recent structural studies have revealed that auxin functions through a “molecular glue” mechanism to enhance protein-protein interactions with the assistance of another small molecule co-factor inositol hexakisphosphate. Given the extensive repertoire of similar ubiquitin ligases in eukaryotic cells, this novel and widely adopted hormone signaling mechanism in plants may also exist in other organisms.

Green Biology

Through our studies of the ubiquitin ligase-based plant hormone receptors, we become immensely interested in plant biology, and particularly how plant hormones act and control the growth and development of this unique kingdom of green living organisms. We believe that our structural biology approach can be effectively applied to the ever-growing studies of plants and make significant contributions and impacts to the field.

Just as our ancestors extracted numerous medicines from plants, we expect to learn many important lessons from plants, which will both advance our understanding of human biology and expedite drug discovery and development. Of equal importance, we envision that the 21st century will witness a second Green Revolution, where modern biology approaches will be used on plants and microbes to develop new technologies for protecting the deteriorating environment, resolving the emerging food crisis, and exploring alternative energy sources.


  • Zhou F, Lin Q, Zhu L, Ren Y, Zhou K, Shabek N, Wu F, Mao H, Dong W, Gan L, Ma W, Gao H, Chen J, Yang C, Wang D, Tan J, Zhang X, Guo X, Wang J, Jiang L, Liu X, Chen W, Chu J, Yan C, Ueno K, Ito S, Asami T, Cheng Z, Wang J, Lei C, Zhai H, Wu C, Wang H*, Zheng N*, Wan J*. 2013. D14-SCFD3-dependent degradation of D53 regulates strigolactone signalling. Nature. 504:406-10. (*Co-correspondence).