Two chimeric mutant genes derived from rev of human immunodeficiency virus type 1 and rex of human T-cell leukemia virus type I were constructed to investigate the functions of the nucleolar-targeting signals (NOS) in Rev and Rex proteins. A chimeric Rex protein whose NOS region was substituted with the NOS of Rev was located predominantly in the cell nucleolus and functioned like the wild-type protein in the Rex assay system. However, a chimeric Rev with the NOS of Rex abolished Rev function despite its nucleolar localization. This nonfunctional nucleolar-targeting chimeric protein inhibited the function of both Rex and Rev. In the same experimental conditions, this mutant interfered with the localization of the functional Rex in the nucleolus.
ASJC Scopus subject areas
- Insect Science