Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems (Probable). The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction (Probable). Involved in the regulation of plant architecture, panicle erectness, panicle and grain length, grain weight, and grain yield (PubMed:19305410, PubMed:19407986, PubMed:19546322). Involved in the regulation of grain size (PubMed:29487318, PubMed:32111163). G proteins are composed of 3 units, alpha, beta and gamma. Expressed in the inflorescence meristem and intercalary meristem (PubMed:19305410). Expressed in the bract primordia of primary and secondary rachis branches (PubMed:19305410). Semi-dwarf phenotype (PubMed:19305410, Ref.2). Dense and erect panicles, and high grain number per panicle (PubMed:19305410, PubMed:32111163). Increased number of spikelets (Ref.2). Increased tolerance to drought, salt and cold stresses (PubMed:32111163). Involved in tolerance to cadmium and copper ions (PubMed:24163402). Seedlings overexpressing DEP1 exhibit enhanced tolerance to cadmium (PubMed:24163402).