Title : Characterization of the murine alpha interferon gene family
Abstract :
- Mouse and human genomes carry more than a dozen genes coding for closely related alpha interferon (IFN-alpha ) subtypes
- IFN-alpha , as well as IFN-beta , IFN-kappa , IFN-epsilon , and limitin , are thought to bind the same receptor , raising the question of whether different IFN subtypes possess specific functions
- As some confusion existed in the identity and characteristics of mouse IFN-alpha subtypes, the availability of data from the mouse genome sequence prompted us to characterize the murine IFN-alpha family
- A total of 14 IFN-alpha genes were detected in the mouse genome, in addition to three IFN-alpha pseudogenes
- Four IFN-alpha genes ( IFN-alpha1 , IFN-alpha7 /10, IFN-alpha8 /6, and IFN-alpha11 ) exhibited surprising allelic divergence between 129/Sv and C57BL/6 mice
- All IFN-alpha subtypes were found to be stable at pH 2 and to exhibit antiviral activity
- Interestingly, some IFN subtypes ( IFN-alpha4 , IFN-alpha11 , IFN-alpha12 , IFN-beta , and limitin ) showed higher biological activity levels than others, whereas IFN-alpha7 /10 exhibited lower activity
- Most murine IFN-alpha turned out to be N-glycosylated
- However, no correlation was found between N-glycosylation and activity
- The various IFN-alpha subtypes displayed a good correlation between their antiviral and antiproliferative potencies, suggesting that IFN-alpha subtypes did not diverge primarily to acquire specific biological activities but probably evolved to acquire specific expression patterns
- In L929 cells, IFN genes activated in response to poly(I*C) transfection or to viral infection were, however, similar