Plant hormone signalling through the eye of the mass spectrometer

Abstract

Plant growth and development are regulated by hormones and the associated signalling pathways share several common steps, the first being the detection of the signal by receptor proteins. This typically leads to conformational changes in the receptor, thereby modifying its spectrum of interaction partners. Next, secondary signals are transmitted via rapid post-translational cascades, such as targeted phosphorylation or ubiquitination, resulting in the activation/deactivation, relocalization or degradation of target proteins. These events finally give rise to the signal-dependent read-out, such as changes in gene expression and regulation of protein activity. So far, the majority of studies aimed at unravelling hormone signalling pathways in plants relied on genetic or transcriptomic approaches. During the last decade however, MS-driven proteomic methods became increasingly popular tools in plant research as they reveal the specific mechanisms controlled by phytohormones, which for a large part occur on the level of the proteome. Here, we provide an up-to-date review on the growing body of work in these areas using MS-based techniques, with a focus on nonpeptide plant hormones.

A Quantitative Proteomic Analysis of Brassinosteroid-induced Protein Phosphorylation in Rice (Oryza sativa L.)

“…Phytohormone signaling is majorly transferred via protein phosphorylation cascades (Walton et al, 2015). In an effort to explore the roles of protein phosphorylation in BR signaling, we profiled the phosphoproteome of Nipponbare ( Oryza sativa L. ssp japonica ) 14 DAG (Day After Germination) seedlings by using a quantitative, label-free phosphoproteomic approach.…”

A Quantitative Profiling Method of Phytohormones and Other Metabolites Applied to Barley Roots Subjected to Salinity Stress

“…Thus, continuous improvements of analytical techniques for phytohormone detection and quantitation are required to study phytohormones in tissues which contain low concentrations of phytohormones. In recent years, high performance liquid chromatography coupled to tandem mass spectrometry (LC-MS) has become the most efficient method to measure phytohormones (Chiwocha et al, 2003; Ljung et al, 2010; Pan et al, 2010; Du et al, 2012; Trapp et al, 2014; Walton et al, 2015). However, most phytohormone quantification studies use plant leaf material which often contains higher concentrations of phytohormones than other tissues (Davies, 2010).…”

Exploring the protein–protein interaction landscape in plants

“…In recent years, the affinity‐based methods have been considerably improved, mostly thanks to the increased sensitivity of MS and the application of novel bioinformatics approaches for accurate data analysis (Armean, Lilley, & Trotter, ; Qu et al, ; Walton, Stes, De Smet, Goormachtig, & Gevaert, ). Single‐tag AP‐MS is widely used in large‐scale studies.…”

“…In recent years, the affinity-based methods have been considerably improved, mostly thanks to the increased sensitivity of MS and the application of novel bioinformatics approaches for accurate data analysis (Armean, Lilley, & Trotter, 2013;Qu et al, 2017;Walton, Stes, De Smet, Goormachtig, & Gevaert, 2015). One of the shortcomings of the single-step purification methods is the identification of large amounts of non-specifically bound proteins that interact either with the solid-phase support, the affinity reagent, or the epitope tag and that are difficult to distinguish from true interactors.…”