Mutational analysis of the human T-cell leukemia virus type I trans-acting rex gene product.
Expression of the human T-cell leukemia virus type I (HTLV-I) rex gene is a prerequisite for the expression of the retroviral structural proteins. We have generated internal deletion mutants of this 27-kDa nucleolar trans-acting gene product to define functional domains in the Rex protein. The phenotype of the various mutant proteins was tested on the homologous HTLV-I rex response element sequence and the heterologous human immunodeficiency virus type 1 (HIV-1) rev response element sequence. Our results indicate that a region between amino acid residues 55 and 132 in the 189-amino-acid Rex protein is required for Rex-mediated trans activation on both retroviral response element sequences. In addition, substitution of the Rex nuclear localization signal by a sequence of the HIV-1 rev gene product targets the Rex protein to the correct subcellular compartment required for Rex function.
Hofer
L
L
Sandoz Research Institute, Vienna, Austria.
Weichselbraun
I
I
Quick
S
S
Farrington
G K
GK
Böhnlein
E
E
Hauber
J
J
D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000648:ultrastructure; D002478:Cells, Cultured; D005786:Gene Expression Regulation; D016370:Gene Products, rex / Q000737:chemistry / Q000235:genetics; D016355:Genes, pX; D015757:Genes, rev; D015368:Human T-lymphotropic virus 1 / Q000235:genetics*; D008969:Molecular Sequence Data; D016296:Mutagenesis
D016370:Gene Products, rex