HIV-1 gRNA, a biological substrate, uncovers the potency of DDX3X biochemical activity.

In this study, we investigated DDX3 biochemical properties in the context of a biological substrate. DDX3 was overexpressed, purified and its enzymatic activities as well as its RNA binding properties were characterized using both model substrates and a biological substrate, HIV-1 gRNA. Biochemical characterization of DDX3 in the context of a biological substrate identifies HIV-1 gRNA as a rare example of specific substrate and unravels the extent of DDX3 ATPase activity. Analysis of DDX3 binding capacity indicates an unexpected dissociation between its binding capacity and its biochemical activity. We further demonstrate that interaction of DDX3 with HIV-1 gRNA relies both on specific RNA determinants and on the disordered N- and C-terminal regions of the protein. These findings shed a new light regarding the potentiality of DDX3 biochemical activity supporting its multiple cellular functions. PMID: 30910425 [PubMed - as supplied by publisher]
Source: Biochimie - Category: Biochemistry Authors: Tags: Biochimie Source Type: research