Post-transcriptional inhibition of the interleukin-1 binding protein B15R of vaccinia virus after coexpression of the related T1 protein.

The interleukin-1 binding B15R protein of Vaccinia virus and murine T1 are related extracellular glycoprotein with similarity to the extracellular domain of interleukin-1 receptors. In cells infected with a recombinant Vaccinia virus directing the overexpression of T1, production of the endogenous viral B15R protein is abrogated. T1 synthesis specifically interferes with the production of B15R, but not of other secretory viral proteins. Inhibition of B15R expression occurs at the posttranscriptional level, is exerted in trans and requires the presence of T1 protein in the infected cell. These results suggest a common maturation pathway for the B15R and T1 protein which might also apply to other members of the interleukin-1 receptor family.