G-Protein Phosphorylation: Aspects of Binding Specificity and Function in the Plant Kingdom

Abstract

Plant survival depends on adaptive mechanisms that constantly rely on signal recognition and transduction. The predominant class of signal discriminators is receptor kinases, with a vast member composition in plants. The transduction of signals occurs in part by a simple repertoire of heterotrimeric G proteins, with a core composed of α-, β-, and γ-subunits, together with a 7-transmembrane Regulator G Signaling (RGS) protein. With a small repertoire of G proteins in plants, phosphorylation by receptor kinases is critical in regulating the active state of the G-protein complex. This review describes the in vivo detected phosphosites in plant G proteins and conservation scores, and their in vitro corresponding kinases. Furthermore, recently described outcomes, including novel arrestin-like internalization of RGS and a non-canonical phosphorylation switching mechanism that drives G-protein plasticity, are discussed.

Proteome-wide analysis reveals G protein-coupled receptor-like proteins in rice ( Oryza sativa )

“…Thus, in the case of plants, the interactome of the heterotrimeric complex is not restricted to 7TM receptors and RGS proteins but also encompasses distinct non-7TM receptors and effectors that seemingly regulate the G protein switch through an intricate posttranslational code. 71 In contrast, another compendium of research substantiates the occurrence of a subset of 7TM receptors in addition to RGS proteins in plants. However, the plausible variations in the canonical theme might be due to the obvious differences in the biology of plants and animal systems.…”

QTL cluster analysis and marker development for kernel traits based on DArT markers in spring bread wheat (Triticum aestivum L.)

“…TraesCS4A02G293900, TraesCS4A02G294000, and TraesCS4A02G303500 were the candidate genes for TKW, and the orthologs were Os03g0669100, At4g34460, and At3g21510, respectively. Among these genes, Os03g0669100 and At4g34460 encoded a regulator of G-protein signaling (RGB1 and AGB1) (Oliveira et al, 2022), and At3g21510 (AHPs) and its encoded protein are related to the regulation of endosperm growth (Tran et al, 2021). RGB1, AGB1, and AHPs were involved in the regulation of grain traits .…”

Map based cloning ofCT2and the pilot functional exploration in abiotic stress

“…For example, plant genomes encode significantly scarce subunits of each G protein, which does not affect its implication in many plant phenotypes [20]. The function of GPCRs is mainly exerted by signal receptor-like kinases with single transmembrane domains in plants, not by 7TM-GPCRs [25][26][27][28][29]. GPCR-like proteins in plants lack classical GEF activity but possess self-activating activity, and the G protein signaling is controlled through the level of protein deactivation [30][31][32][33].…”