INFLUENZA-VIRUSES AND CELL-MEMBRANES

Influenza viruses are spherical, about 1000 Angstrom in diameter, and consist of an as yet undefined central structure containing the eight negative-sense RNA molecules of the genome (1) in association with the transcriptase required for mRNA synthesis, an abundant nucleoprotein, and an equally abundant matrix protein. This core is surrounded by a membrane derived from the cell surface in a budding process by which n ewly formed viruses are released from the infected cell. During infect ion cell membranes are modified by the incorporation of newly synthesi zed virus membrane proteins, and the finally released viruses contain exclusively two different types of virus-specified glycoprotein, hemag glutinin and neuraminidase, and a proton channel protein, M(2). All th ree of these molecules have been studied extensively, particularly the glycoproteins, and in this paper information on their structures and functions will be summarized and related to modifications in cellular membranes that occur during virus infection.