722 / 2019-05-09 15:21:07

The role of oxygen and nitric oxide sensing in plant responses to the environment

abiotic stress,ubiqutin,Molecular oxygen,nitric oxide,proteostasis

全体主题 > Abiotic Stress

Although much is known about molecular mechanisms of signal transduction as part of plant responses to abiotic stresses, little is still known about how these stresses are sensed. I will discuss our current approaches to understand how oxygen- and nitric oxide- (NO) sensing via the Cys branch of the PRT6 N-degron pathway acts as an overarching key component of plant sensing and response to multiple abiotic stresses. N-degron pathways (previously the 'N-end rule pathway') represent ancient conserved components of the Ubiquitin Proteasome System (UPS), that have profound effects on proteostasis. They relate the identity of the amino-terminal (Nt-) residue of a protein to its destruction by the UPS. Our work uncovered a simple biochemical mechanism that higher plants use to simultaneously sense oxygen and nitric oxide (NO), through amino-terminal Cys of substrates via the PRT6 N-degron pathway [1,2], and substrates so far identified are the ERFVII transcription factors [1] and the PRC2 component VERNALISATION2 [3]. This homeostatic response mechanism links changes in oxygen and NO levels to physiological and developmental outputs and is used by plants to measure and respond to important environmental changes associated with abiotic stress and changes in seasons [3,4,5].

1. Gibbs et al Nature 2011; 2. Gibbs et al Molecular Cell 2014; 3. Gibbs et al Nature Communications 2018; 4. Abbas et al Current Biology 2015; 5. Vicente et al Current Biology 2017