Plays a role in RNA transcription or processing during stress. Binds RNAs and DNAs sequence with a preference to single-stranded nucleic acids. Displays strong affinity to poly(U) and poly(G) sequence. Involved in mRNA alternative splicing of numerous targets by modulating splice site selection. Negatively regulates the circadian oscillations of its own transcript as well as RBG8 transcript. Forms an interlocked post-transcriptional negative feedback loop with the RBG8 autoregulatory circuit. Both proteins negatively autoregulate and reciprocally crossregulate by binding to their pre-mRNAs and promoting unproductive splicing coupled to degradation via the NMD pathway. Involved in the regulation of abscisic acid and stress responses. Affects the growth and stress tolerance under high salt and dehydration stress conditions, and also confers freezing tolerance, particularly via the regulation of stomatal opening and closing in the guard cells. Exhibits RNA chaperone activity during the cold adaptation process. Involved in the export of mRNAs from the nucleus to the cytoplasm under cold stress conditions. Target of the Pseudomonas syringae type III effector HopU1, which could probably be involved in plant innate immunity. Component of the flowering autonomous pathway which promotes floral transition, at least partly by down-regulating FLC. Mediates cell-to-cell trafficking of RNA interference (RNAi) signals (small RNAs (sRNA), e.g. small interfering RNA (siRNA) and microRNA (miRNA)) which regulate growth and development, as well as responses to environmental inputs, including pathogen attack; can compromise zucchini yellow mosaic virus (ZYMV) and tobacco rattle virus (TRV) infections at the early stage (PubMed:31812689). Interacts with TRN1 (PubMed:14756317). Interacts with the Pseudomonas syringae type III effector HopU1 (PubMed:22013065). Binds to small phloem-mobile single-stranded RNAs (ss-sRNA, e.g. small interfering RNA (siRNA) and microRNA (miRNA)) in the phloeme exudate, including viral-derived sRNA (vsiRNA) (PubMed:31812689). Shuttling between nucleus and cytoplasm. Relocalization from the cytoplasm into the nucleus is mediated by TRN1. Observed in the phloem translocation stream (PubMed:31812689). Ubiquitous with strong expression in guard cell. Up-regulated by cold stress and down-regulated by dehydration stress, salt stress, abscisic acid (ABA) and mannitol. Circadian regulation. Induced by hydrogen peroxide (at the protein level). Up-regulated under P.carotovorum SCC1 (Pec) infection. The glycine-rich (GR) domain is necessary and sufficient for cell-to-cell movement and to interefere with zucchini yellow mosaic virus (ZYMV) infection. N-terminal part of the protein is one of the crucial determinant to confer RNA chaperone activity during cold adaptation process. ADP-ribosylated by the Pseudomonas syringae type III effector HopU1. ADP-ribosylation reduces the ability of the protein to bind RNA. Hypersensitive responses to ABA in both seed germination and root growth. Late-flowering. Increased germination rate and seedling growth under salt and dehydration stress. Impaired mRNA export under cold stress conditions. Defective in PAMP-triggered immunity (PTI) responses and high susceptibility to P.syringae and P.carotovorum SCC1 (Pec). Increased sensitivity to tobacco rattle virus (TRV) (PubMed:31812689). The triple mutant srbp1 srbp2 srbp3 is more susceptible to TRV (PubMed:31812689). Plants overexpressing RBG7 display retarded germination and affected seedling growth under salt and dehydration stress conditions, confer freezing tolerance and also possess enhanced resistance to P.syringae. May be due to a competing donor splice site. Belongs to the GR-RBP family. Wrong choice of frame. Wrong choice of frame. Wrong choice of frame.