May play a role in virus budding. Exerts cytotoxic effects by activating a mitochondrial apoptotic pathway through M ectodomain. May display a viroporin activity. Binds to host cell surface receptor and mediates fusion between viral and cellular membranes (PubMed:20949067). Envelope protein is synthesized in the endoplasmic reticulum in the form of heterodimer with protein prM (By similarity). They play a role in virion budding in the ER, and the newly formed immature particle is covered with 60 spikes composed of heterodimer between precursor prM and envelope protein E (By similarity). The virion is transported to the Golgi apparatus where the low pH causes dissociation of PrM-E heterodimers and formation of E homodimers (By similarity). prM-E cleavage is inefficient, and many virions are only partially matured (By similarity). These uncleaved prM would play a role in immune evasion (By similarity). Involved in immune evasion, pathogenesis and viral replication. Once cleaved off the polyprotein, is targeted to three destinations: the viral replication cycle, the plasma membrane and the extracellular compartment. Essential for viral replication. Required for formation of the replication complex and recruitment of other non-structural proteins to the ER-derived membrane structures. Excreted as a hexameric lipoparticle that plays a role against host immune response. Antagonizing the complement function. Binds to the host macrophages and dendritic cells. Inhibits signal transduction originating from Toll-like receptor 3 (TLR3). Disrupts the host endothelial glycocalyx layer of host pulmonary microvascular endothelial cells, inducing degradation of sialic acid and shedding of heparan sulfate proteoglycans. NS1 induces expression of sialidases, heparanase, and activates cathepsin L, which activates heparanase via enzymatic cleavage. These effects are probably linked to the endothelial hyperpermeability observed in severe dengue disease. Homodimer; in the endoplasmic reticulum and Golgi. Interacts with protein prM. Interacts with non-structural protein 1. Homodimer; Homohexamer when secreted. Interacts with envelope protein E. Located in RE-derived vesicles hosting the replication complex. The transmembrane domains of the small envelope protein M and envelope protein E contain an endoplasmic reticulum retention signal. N-glycosylated. N-glycosylated. The excreted form is glycosylated and this is required for efficient secretion of the protein from infected cells. Specific enzymatic cleavages in vivo yield mature proteins. Cleavages in the lumen of endoplasmic reticulum are performed by host signal peptidase, wereas cleavages in the cytoplasmic side are performed by serine protease NS3. Signal cleavage at the 2K-4B site requires a prior NS3 protease-mediated cleavage at the 4A-2K site.