%0 Journal Article %A Richard-Molard, Christine %A Blondel, Danielle %A Wyers, Françoise %A Dezelee, Sybille %T Sigma Virus: Growth in Drosophila melanogaster Cell Culture; Purification; Protein Composition and Localization %D 1984 %J Journal of General Virology, %V 65 %N 1 %P 91-99 %@ 1465-2099 %R https://doi.org/10.1099/0022-1317-65-1-91 %K structural proteins %K sigma virus %K Drosophila cells %I Microbiology Society, %X SUMMARY The growth cycle of sigma virus in Drosophila melanogaster cells was studied: optimal virus production was reached about 40 h after infection; virus release declined thereafter and then remained approximately constant (carrier state). In the presence of DEAE-dextran during virus adsorption, more cells became infected and sigma virus production was enhanced. Sigma virus was partially purified by a gentle procedure. Five presumptive virus-specific proteins with molecular weights 210K, 68K, 57K, 44K and 25K were observed. The p68 polypeptide was glycosylated and formed the spikes of the virion particles. The nucleocapsid contained a single major protein, p44, and one or two minor proteins (p210 and probably p57); another protein, p25, was more loosely associated with the nucleocapsid. None of these proteins was found to be phosphorylated. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-65-1-91