Figure 6: Model of the nucleotide exchange mechanism by Mon1–Ccz1. | Nature Communications

Figure 6: Model of the nucleotide exchange mechanism by Mon1–Ccz1.

From: Architecture and mechanism of the late endosomal Rab7-like Ypt7 guanine nucleotide exchange factor complex Mon1–Ccz1

Figure 6

(a) F33 of Ypt7 interacts with the guanosine base to stabilize nucleotide binding. Switch I closes the binding pocket with Y37 and K38 solvent exposed. (b) F33 and Y37 are fixed in hydrophobic pockets on Mon1–Ccz1, leading to switch I rearrangement and opening of the nucleotide-binding pocket. In addition, K38 of Ypt7 is inserted into the nucleotide pocket, repelling with its positively charged terminal amine group the Mg2+ cofactor ion from the binding site.

Back to article page