Figure 1. Dengue virus (DENV2) can cleave human but not nonhuman primate STING.

(A) A phylogeny of select primate species, showing the three main simian clades: apes, Old World monkeys, and New World monkeys (Perelman et al., 2011). The primate species from which STING is tested in this study are shown with purple arrows. Possible primate reservoir hosts for sylvatic dengue viruses, based on virus isolation from sentinel monkeys, or antibody detection, are shown in red (Africa) and green (Asia). The current evidence for these primate reservoir hosts is reviewed in the discussion section. (B) 293T cells were cotransfected with plasmids encoding STING-HA, and the NS2B3-Flag protease complex with or without the S135 inactivating mutation. Whole cell lysate isolated 24 hr post transfection was run on a protein gel and immunoblotted with anti-Flag or anti-HA antibodies. The encoded NS2B-NS3-Flag polyprotein auto-processes into the NS2B3 protease complex if the protease is active, as seen in the anti-Flag blot where in some samples the NS3-Flag protein has been liberated through cleavage. We sometimes see lower bands underneath the full-length mouse STING, but conclude that they are endogenous degradation products since they are equal in intensity in the presence of the active or dead protease.

Figure 1—figure supplement 1. Many primate species reside in areas where dengue viruses are endemic in humans.