Is associated with a DNA binding complex that binds to the G box, a well-characterized cis-acting DNA regulatory element found in plant genes (PubMed:7972511, PubMed:7870824, PubMed:16407442). Involved in the regulation of nutrient metabolism (PubMed:22104211, PubMed:21094157). Reciprocal negative transcription regulation of miR396 (PubMed:22751317). Negative regulator of constitutive freezing tolerance and cold acclimation by controlling cold-induced gene expression partially through an ethylene (ET)-dependent pathway; prevents ethylene (ET) biosynthesis, probably by binding 1-aminocyclopropane-1-carboxylate synthases (ACS) to reduce their stability, thus contributing to establish adequate ET levels under both standard and low-temperature conditions (PubMed:25122152). Component of a DNA binding complex that binds to the G box (PubMed:16407442). Interacts with IDH3, AGT3, GLN1-1, GLN1-2, GLN1-4, SAM1, SAM2, MDH1, METK3 and MDH2 (PubMed:22104211, PubMed:21094157). Binds to 1-aminocyclopropane-1-carboxylate synthases (ACS) such as ACS2, ACS5, ACS6, ACS8, and ACS11 (PubMed:25122152). Interacts with FD (PubMed:25661797). Interacts with DREB1A and DREB1B in the nucleus (PubMed:28344081). Interacts with CINV1 (PubMed:25256212). Translocates from the cytosol to the nucleus when phosphorylated. By cold in an abscisic acid- (ABA-) independent manner (at protein level) (PubMed:7520301, PubMed:25122152). Repressed by phosphate (Pi) deprivation (PubMed:17598127). Induced by nitrogen (N) and phosphate (P) deprivation in leaves, but repressed by potassium (K) and N deprivation in roots (PubMed:21094157). Repressed by miR396 (PubMed:22751317). Short primary roots and reduced size, with smaller cells (PubMed:21094157, PubMed:25122152). Disturbed levels of several metabolites (e.g. beta-alanine, threonic acid, phenylalanine, 1,3-diaminopropane dihydrochloride, citrate, glycine, aspartate, glucose, 1,4-diaminobutane, proline, palmitate and shikimate) (PubMed:22104211). Increased miR396 levels in plants lacking simultaneously GRF1, GRF2 and GRF3 (PubMed:22751317). Higher freezing tolerance, and greater levels of cold-inducible genes and ethylene- (ET-) inducible genes leading to higher ET levels, as well as slightly enhanced expression of ACS6 (PubMed:25122152). Belongs to the 14-3-3 family.