Fig.1 JEV virus structure and genome. (Singh, et al., 2012)
Japanese encephalitis virus (JEV), a member of the genus Flavivirus, family Flaviviridae, is an enveloped positive-strand RNA virus. JEV is the etiological agent of Japanese encephalitis (JE), a serious neurological disease characterized by extensive inflammation in the central nervous system. While most infections cause little or no symptoms, brain inflammation does occur on occasion. An estimated 35,000-50,000 cases are reported each year, with 20-30% of patients dying and 30-50% of survivors suffering from neurological sequelae.
The JEV virion has an icosahedral-shaped lipid-covered outer capsid and is roughly spherical in shape, measuring 50 nm in diameter. JEV comprises a single-stranded, linear, positive-sense RNA genome, ~ 11 kb in length. A single ORF is translated into a 3,432 amino acid unsegmented polyprotein, which is then cleaved to yield functional proteins. The polyprotein is cleavaged to form three structural proteins (capsid, C; pre-membrane, M; and envelope, E) and several nonstructural proteins (NS1, NS2a, NS2b, NS3, N4a, NS4b, NS5).
Fig.2 Structures of the JEV virion, JEV genome, and polyprotein. (Bhardwaj, et al., 2020)
The structural proteins are essential for viral particle assembly and egress. The capsid binds to viral RNA, forming a nucleocapsid. The smooth outer protein shell is formed by E proteins, and the M proteins are buried beneath it. The prM is involved in folding the E protein. E proteins are responsible for cellular attachment and have a hydrophobic loop that mediates viral-host membrane fusion.
Non-structural proteins are essential for viral replication. Because its N-terminal domain (methylase domain) has methylase activity and its C-terminal domain has RNA-dependent RNA polymerase (RdRp) activity, NS5 is a critical protein. Like NS3, NS5 is a multi-enzymatic protein. NS3 and NS5 catalyze viral RNA replication. During replication, the hydrophobic NS4A coordinates with NS1; however, the function of this alignment is unknown.
JEV comprises five genotypes (GI-GV). Until 1990, GIII was the most common genotype causing human and animal diseases. However, over the last decade, JEV GI has surpassed GIII as the dominant genotype in Asia's traditional epidemic areas. GII is primarily found in Southeast Asia and northern Australia, whereas GIV and GV are mostly found in Southeast Asia's tropical regions.
Creative Biolabs' team possesses in-depth expertise in antibody generation and lead-candidate selection. As an expert in the antibody field, we now provide numerous anti-JEV antibodies targeting various proteins such as NS1, NS2, env, etc. We also provide a fully comprehensive suite of secondary antibodies and isotype controls to meet your needs. In addition, we have the ability to provide comprehensive services for specific project needs, including antibody discovery, engineering, and customized services. Please feel free to contact us for further information.