Influenza virus representation

There is a wide variety of vectors used to deliver DNA or oligonucleotides into mammalian cells, either in vitro or in vivo. The most common vector systems are based on viral [retroviruses (9, 10), adeno-associated virus (AAV) (11), adenovirus (12, 13), herpes simplex virus (HSV) (14)] andnonviral [cationic liposomes (15,16), polymers and receptor-mediated polylysine-DNA] complexes (17). Other viral vectors that are currently under development are based on lentiviruses (18), human cytomegalovirus (CMV) (19), Epstein-Barr virus (EBV) (20), poxviruses (21), negative-strand RNA viruses (influenza virus), alphaviruses and herpesvirus saimiri (22). Also a hybrid adenoviral/retroviral vector has successfully been used for in vivo gene transduction (23). A simplified schematic representation of basic human gene therapy methods is described in Figure 13.1. 

Only Type A influenza vims has been found to be capable of producing pandemics. The influenza A virus is identified as a medium-size RNA virus, some lit) nanometers in diameter and delimited by a membrane of lipids and polysaccharides derived from the host cell and virus-specific protein. Five distinct proteins have been identified, three of which are inside the virion. A schematic representation of the influenza virus emerging from a cell is given in Fig. 2. 

Fig. 2. Schemaiic representation of an influenza virus emerging from a cell. After Kilbourne)...

Fig. 2. Schematic representation of the influenza virus and the action of sialidase in the continued replication cycle (modified from Moscona33).

Fig. 3. A schematic representation of some key interactions of Neu5Ac2en 5 with conserved influenza virus A sialidase active site residues.

Fig. 5-7 A diagrammatic representation of the hemagglutinin trimer from the influenza virus.

Fig. (2). Schematic representation of an influenza virus (Stryer, Biochimica, Zanichelli Editore).

Fig.1. Viruses. Schematic representation of virus particles, all drawn to scale. The type of genome (RNA or DNA) is shown in brackets. Enveloped viruses 1 Pox virus (DNA). 2 Rabies virus (RNA). 3 Influenza virus (RNA). 4 Measles virus (RNA). 5 Chickenpox virus (ONA). Naked or unenveloped viruses 6 Yellow fever virus (RNA). 7 Adenovirus (DNA). 8 Reovirus (RNA). 9 Wart-papilloma virus (ONA). 10 Poliomyelitis virus (RNA). 11 Parvovirus (RNA). 12 Corona virus (RNA). 13 Tobacco mosaic virus (RNA). 14 Bacteriophage T2 (DNA).

Figure 11 (Left) Scheme of the polymerized bilayer assembly. The blue phase polydiyacetylene chromatic detection element is deposited over a support monolayer. The polydiacetylene chain Is asymmetrically substituted with urethane side groups partially terminated with receptor-binding ligands. (Right) Absorption spectrum of the blue and red phase PDA with a schematic representation of their chain with (red phase) and without (blue phase) influenza virus attached. Adapted figures with permission from D.H. Charych, J.O. Nagy, W. Spevak, and M.D. Bednarski, Sc/ence 261, 585 (1993), Figure 2 and 3. Copyright 1993 AAAS.

Fig. 9 Diagrammatic representation of influenza A virus active site indicating the amino acid residues that have shown mutation under drug pressure. Oseltamivir carboxylate 18 is shown in the active site...

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