Activity of rat Mx proteins against a rhabdovirus

Abstract

Upon stimulation with alpha/beta interferon, rat cells synthesize three Mx proteins. Sequence analysis of corresponding cDNAs reveals that these three proteins are derived from three distinct genes. One of the rat cDNAs is termed Mxl because it is most closely related to the mouse Mxl cDNA and because it codes for a nuclear protein that, like the mouse Mxl protein, inhibits influenza virus growth. However, this protein differs from mouse Mxl protein, in that it also inhibits vesicular stomatitis virus (VSV), a rhabdovirus. A second rat cDNA is more closely related to the mouse Mx2 cDNA and directs the synthesis of a cytoplasmic protein that inhibits VSV but not influenza virus. The third rat cDNA codes for a cytoplasmic protein that differs from the second one in only eight positions and has no detectable activity against either virus. These results indicate that rat Mx proteins have antiviral specificities not anticipated from the analysis of the murine Mxl protein.

Differential expression of immunoregulatory genes in male and female Norway rats following infection with Seoul virus

“…The rat Mx2 and Mx3 genes are 98% similar and the respective proteins differ by only eight amino acids [Lee and Vidal, 2002]. Using plasmids containing rat Mx1, Mx2, or Mx3 [Meier et al, 1990], PCR primers were designed that were specific for each Mx gene and that did not cross-react with the other Mx genes. Quantitative RT-PCR data revealed that Mx2, and to a lesser extent Mx1, was downregulated in male rats 15 days after infection (Fig.…”

Interferon‐inducible Mx proteins in fish

“…Murine Mxl synthesized in insect cells via a baculovirus expression system was purified to homogeneity (47) and found to aggregate into dimers and trimers. The aggregating properties of Mx had previonsly been suggested by immunofluorescence studies on the cytoplasmie human Mx proteins and the nuclear mouse and rat Mx proteins, all of which stain as distinctly punctate aggregates (61)(62)(63)(64)(65)4). Large Mxl aggregates were observed in the nuclei of interferon-treated A2G cells under immunoelectroii-microscopic examination.…”

“…Rat Mxl is localized in the nucleus and shares 79% amino acid identity with the nuclear murine Mxl. Rat Mx2 and Mx3 are cytoplasmie proteins and differ from each other by only eight amino acids (7). When 3T3 cells were microinjected with expression plasmids for rat Mxl, Mx2, or Mx3 and challenged with influenza virus or VSV, the rat Mxl strongly inhibited influenza virus production and to a lesser degree inhibited VSV production.…”

“…It is the last set of proteins, named Mx for their role in myxovirus resistance, that will be the subject of this review. Mx inhibition of negative-stranded RNA viruses has been well estabhshed (4)(5)(6)(7), although the meclianism{s) by which these proteins effect intracellular resistance is not dearly understood. Specific Mx proteins have heen associated with resistance to different viruses in mammals efforts to identify the protein component responsible for the resistance to the different viruses have yielded information regarding their nuclear and cytoplasmic localization, guanosine triphosphatase activity, and intraceliular protein hinding activity.…”

Vesicular stomatitis virus transcription is inhibited by TRIM69 in the interferon-induced antiviral state

“…A number of ISGs including Mx1, PKR, IFITM3, and tetherin have previously been reported to inhibit VSV replication (21)(22)(23)(24). However, it was not known whether this list represents a complete catalogue of ISGs proteins with anti-VSV activity.…”