(a) Schematic representation of domain structures in plant glycine-rich RNA-binding proteins (GR-RBPs). Members of class I have an RNA recognition motif (RRM) at the N-terminus and a glycine-rich region at the C-terminus. Class II proteins, which are also called zinc finger-containing glycine-rich RNA-binding proteins (RZs), contain an RRM and a glycine-rich region separated by a CCHC-type zinc finger motif. Members of class III have an N-terminal cold shock domain (CSD) and a C-terminal glycine-rich region with two or more zinc finger motifs while class IV proteins have two RRMs and a glycine-rich region at the C-terminus. (b) Phylogenetic tree based on the alignment of protein sequences of GR-RBPs from sixteen plant species. These GR-RBPs are divided into four subclasses (denoted I–IV). Phylogenetic analyses were conducted in MEGA5. Species names are abbreviated as follows: Sl, Solanum lycopersicum; Bn, Brassica napus; Nt, Nicotiana tabacum; At, Arabidopsis thaliana; Cs, Camelina sativa; Ca, Capsicum annuum; Sb, Sorghum bicolor; Mh, Malus hupehensis; Hv, Hordeum vulgare; Cs, Cucumis sativa; Ca, Capsicum annuum; Os, Oryza sativa; Lp, Lolium perenne; Lb, Limonium bicolor; Ta, Triticum aestivum; It, Ipomoea trifida. (c) Expression profile of GR-RBPs in different tissues of Arabidopsis thaliana. (d) Expression profile of GR-RBPs from Arabidopsis thaliana under different treatments.