Synthesis of Semliki Forest virus RNA polymerase components nsP1 through nsP4 in Saccharomyces cerevisiae by expression of cDNA encoding the nonstructural polyprotein.
نویسندگان
چکیده
A Semliki Forest virus nonstructural polyprotein, P1234, expressed in the yeast Saccharomyces cerevisiae in the absence of a replicative RNA template appeared to be properly cleaved into nsP1 to nsP4. All nsPs were membrane associated, and nsP2 was also transported to the nucleus. The membrane fraction containing nsPs showed guanine-7-methyltransferase and guanylyltransferase-like activities, typical for Semliki Forest virus nsP1.
منابع مشابه
Polyprotein Processing as a Determinant for In Vitro Activity of Semliki Forest Virus Replicase
Semliki Forest virus (SFV) is an arthropod-borne alphavirus that induces membrane invaginations (spherules) in host cells. These harbor the viral replication complexes (RC) that synthesize viral RNA. Alphaviruses have four replicase or nonstructural proteins (nsPs), nsP1-4, expressed as polyprotein P1234. An early RC, which synthesizes minus-strand RNA, is formed by the polyprotein P123 and the...
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ورودعنوان ژورنال:
- Journal of virology
دوره 70 6 شماره
صفحات -
تاریخ انتشار 1996