Guanine nucleotide-binding proteins (G proteins) are involved as a modulator or transducer in various transmembrane signaling systems. The beta and gamma chains are required for the GTPase activity, for replacement of GDP by GTP, and for G protein-effector interaction. G proteins are composed of 3 units, alpha, beta and gamma (By similarity). The heterodimer formed by GNB1 and GNG2 interacts with ARHGEF5 (PubMed:19713215). The heterodimer formed by GNB1 and GNG2 interacts with GRK2 (By similarity). Interacts with ARHGEF18 and RASD2 (PubMed:14512443, PubMed:19255495). Phosphorylation at His-266 by NDKB contributes to G protein activation by increasing the high energetic phosphate transfer onto GDP. The disease is caused by variants affecting the gene represented in this entry. Belongs to the WD repeat G protein beta family.