Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis
Fig 13
Diagram of the kinetic model of ligand, G protein and target enzyme interactions.
Rnd is the desensitized receptor, Rn is the free receptor, Ln is the ligand, LRn is the receptor bound with ligand, LRGnGDP is the receptor bound with ligand and G protein, GnGDP is the G proteins consisting of subunits α, β and γ. In this ground state the α-subunit is bound to GDP. GαnGTP is the GTP-bound α subunit of G protein, Gβγn is the β and γ subunit of G protein, GαnGDP is GDP-bound α subunit of G protein, GαnGTPEn is the complex of the α-subunit carries the GTP and effectors enzyme (En). Efn is the enzyme that is not bound with G protein. The constants can be identified by their subcripts, where n the forward transition and nr is the reverse transition. For reversible reactions (double arrows), forward reactions are in the direction of association. (A) Collision coupling model. (B). Pre-coupling of receptor and G-protein model.