Figure 1.

Scheme of PMT-activated heterotrimeric G proteins and subsequent signaling pathways. PMT activates Gα_i to inhibit adenylyl cyclase (AC). PMT-induced activation of Gα₁₃ and Gα_q stimulates Rho guanine nucleotide exchange factors (RhoGEF) leading to the activation of the low molecular mass GTPase RhoA. Moreover, activation of Gα_q leads to stimulation of the Jak-STAT (Janus kinase, signal transducer and activator of transcription) pathway and the canonical Gα_q effector phospholipase Cβ (PLCβ). By activation of the Gα-subunit, Gβγ is released from the heterotrimeric complex and mediates signaling via βγ-specific effectors, e.g., phosphoinositide-3-kinase (PI3K)γ.