The Neurobiology of Zika Virus Hongda Li, Laura Saucedo-Cuevas, Sujan Shresta, Joseph G. Gleeson  Neuron  Volume 92, Issue 5, Pages 949-958 (December 2016) DOI: 10.1016/j.neuron.2016.11.031 Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 1 Neural Tropism for Zika Virus Determines Site of Pathology ZIKV can cause neurological disease through direct infection of cells or through immune-mediated effects in the case of post-infectious polyradiculopathy (Guillain-Barré syndrome). In the fetus, ZIKV can infect neural progenitor and neural retinal cells, leading to microcephaly and retinal disease. The long-term consequences on cognition are not documented. In adults, infection of neural progenitors in stem cell niches can lead to loss of these populations. Adults can also display post-infectious polyradiculopathy, presumably due to immune activation, as well as uveitis and conjunctivitis. Neuron 2016 92, 949-958DOI: (10.1016/j.neuron.2016.11.031) Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 2 Multiple Mechanisms Used by Zika Virus to Bypass Intrinsic Cellular Antiviral Pathways (A) ZIKV genome and signaling mechanisms. ZIKV cross-section consists of envelope (E), membrane (M), and capsid (C) proteins surrounding the genome. The 10,617-nucleotide ZIKV RNA encodes a polyprotein with three structural proteins, capsid, premembrane/membrane, and envelope, and seven nonstructural proteins, NS1, NS2A, NS2B, NS3, NS4A, NS4B, and NS5. (B) ZIKV enters the host cell through receptor-mediated endocytosis. One candidate receptor is AXL, a receptor tyrosine kinase. Viral RNA is then released and used for synthesis of proteins by co-opting endoplasmic reticulum. ZIKV proteins function to enhance viral replication through blocking two innate pathways that normally inhibit viral replication: interferon (IFN) and mTOR signaling. NS5 protein promotes degradation of the interferon effector STAT2, which would otherwise promote transcription of interferon pathway genes. NS4A and NS4B inhibit mTOR signaling emanating from receptor tyrosine kinases (RTK). These effects of ZIKV proteins also function to inhibit neurogenesis and promote cell death. Neuron 2016 92, 949-958DOI: (10.1016/j.neuron.2016.11.031) Copyright © 2016 Elsevier Inc. Terms and Conditions