Fig. 5
From: Structural determinants of Rab11 activation by the guanine nucleotide exchange factor SH3BP5
Clinically relevant Rab11 mutations disrupt nucleotide-binding or alter SH3BP5 GEF activity. a Point mutations found in developmental disorders mapped on the structure of Rab11 bound to SH3BP5. b In vitro GEF assay of SH3BP5 on clinical Rab11 mutations. Nucleotide exchange was monitored by measuring the fluorescent signal during the SH3BP5 (1–455) (300 nM, 150 nM, or 75 nM) catalyzed release of Mant-GDP from 4 µM of the indicated Rab in the presence of 100 µM GTPγS. Fluorescent measurements were completed every 11 s for a total of 60 min (Excitation λ = 366 nm; Emission λ = 443 nm). c Nucleotide exchange rates of Rab11A mutants plotted as a function of SH3BP5 concentration. The kcat/Km values for all Rab11A mutations were calculated from the slope. Error bars represent SD (n = 3)
