Figure 1. The domain structure of PLCs.
PLC-β consists of an N-terminal PH domain, four EF hands, a catalytic TIM barrel (X + Y), a C2 domain, and a carboxy-terminal (CT) domain. The second PH domain of PLC-γ is split to allow an insert of two SH2 domains and one SH3 domain between X and Y domains. SH2, Src homology 2; SH3, Src homology 3; RA, Ras association; RasGEF, Ras GDP/GTP exchange factor