Guanine nucleotide-binding proteins (G proteins) are involved as modulators or transducers in various transmembrane signaling systems. Involved in behavioral responses to P.aeruginosa by controlling the expression of daf-7, a member of the TGF-beta family, in ASJ sensory neurons. G proteins are composed of 3 units; alpha, beta and gamma. The alpha chain contains the guanine nucleotide binding site. Belongs to the G-alpha family. G(q) subfamily.