Figure 3.

Recycling kinetics of Δ2 vpTR constructs containing point mutations in LL^76–77 or the cluster of acidic amino acids. The average recycling rate constants ± SEM from at least three independent determinations are presented. The data are from representative clonal lines expressing the various constructs. The recycling rate constants of TR and vpTR are presented for comparison. The recycling rate constants of the mutants in the Δ2vpTR background are all different from the recycling rate constant of ΔvpTR with P values < 0.001 (heteroscedastic, two-tailed Student's t test).