Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems. Required for platelet activation. Regulates B-cell selection and survival and is required to prevent B-cell-dependent autoimmunity. Regulates chemotaxis of BM-derived neutrophils and dendritic cells (in vitro) (By similarity). Transduces FFAR4 signaling in response to long-chain fatty acids (LCFAs) (By similarity). Together with GNA11, required for heart development (By similarity). G proteins are composed of 3 units; alpha, beta and gamma. The alpha chain contains the guanine nucleotide binding site. Binds SLC9A3R1. Forms a complex with PECAM1 and BDKRB2. Interacts with PECAM1 (By similarity). Interacts with GAS2L2 (By similarity). Colocalizes with the adrenergic receptors, ADREN1A and ADREN1B, at the nuclear membrane of cardiac myocytes. Palmitoylated by ZDHHC3 and ZDHHC7. Palmitoylation occurs in the Golgi and participates in the localization of GNAQ to the plasma membrane. Histaminylated at Gln-209 residues by TGM2. Belongs to the G-alpha family. G(q) subfamily.