Figure 2: Multimerization of Met and its association with SRC.

(a) Diagramatic representation of BRET assays used in these experiments. Protein A fused to the photon donor Rluc2 and protein B fused to the fluorophore m-Ametrine are expressed in cells. Photons (410 nm) emitted by the Rluc2 substrate are emitted. Upon addition of agonist (orange hexagon) the proteins dimerize. Now, photons emitted by the Rluc2 substrate excite the closely associated and fixed fluorophore and photons are emitted at 535 nm providing an elevated BRET ratio (535 nm emission/410 nm emission). When assessing ligand-mediated dissociation, an elevated BRET ratio exists in the absence of agonist and decreases with agonist addition. (b) Spontaneous multimerization of Met with ligand-dependent dissociation. White bars denote BRET ratios in the absence of methyl farnesoate. Gray bars represent BRET ratios from cells treated with 30 μM methyl farnesoate. (c) Methyl farnesoate-dependent dimerization of the MfR subunits. White bars denote BRET ratios in the absence of methyl farnesoate. Gray bars represent BRET ratios from cells treated with 100 μM methyl farnesoate. All data are presented as the mean and standard deviation (n = 3). An asterisk denotes a significant difference between the control and methyl farnesoate treatment (p < 0.05, Student’s t test).