@article{mbs:/content/journal/jgv/10.1099/0022-1317-67-10-2215, author = "Van Heuvel, Margreet and Bosveld, I. Jaap and Mooren, Arno T. A. and Trapman, Jan and Zwarthoff, Ellen C.", title = "Properties of Natural and Hybrid Murine Alpha Interferons", journal= "Journal of General Virology", year = "1986", volume = "67", number = "10", pages = "2215-2222", doi = "https://doi.org/10.1099/0022-1317-67-10-2215", url = "https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-67-10-2215", publisher = "Microbiology Society", issn = "1465-2099", type = "Journal Article", keywords = "hybrid genes", keywords = "interferon (MuIFN-α) subspecies", keywords = "heterologous expression", abstract = "Summary Four natural murine interferon-α genes (MuIFN-α1, -α2, -α4 and -α6) and four hybrid genes (α1α4, α2α4, α4α1 and α4α2) were transiently expressed in monkey COS cells under the transcriptional control of the simian virus 40 early promoter. The proteins were labelled with [35S]methionine during a 16 h incubation and proteins secreted by the cells during this period were separated by polyacrylamide gel electrophoresis and subsequently visualized by fluorography. Under the conditions used, the IFNs represented 5 to 10% of the total amount of secreted proteins. All genes were found to encode biologically active IFN subspecies, including α4 which has a deletion of five amino acids. When the specific activities of the proteins were compared, it appeared that the specific antiviral activity of α4 on mouse cells was three- to sixfold higher than the activities of the other natural IFN subspecies. The specific activities of the hybrid proteins were similar to those of the natural proteins, except for the α2α4 hybrid which had a higher specific activity than the original proteins. The ability of the natural and hybrid subspecies to protect hamster cells against viral infection was determined using MuIFN-α1 as a standard. Large differences in activity were found, with α6 as the most and α4 as the least active subspecies.", }