| abstract |
A novel retroviral nucleotide sequence comprising a constitutive transport enhancer which functions to transport mRNA transcripts from the nucleus to the cytoplasm of a cell, wherein the mRNA transcript is either differentially spliced, alternatively spliced, incompletely spliced, or unspliced. Additionally disclosed are methods of using the constitutive transport enhancer to screen agents for antiviral activity against rev-dependent HIV proteins by expressing the proteins in a rev-negative subgenomic construct containing the enhancer either in the presence of absence of the agent. Additionally, disclosed are methods of making a constitutive transport enhancer by isolating a sequence to be tested for constitutive transport enhancer activity, inserting the sequence into a vector containing a DNA sequence not normally transported from the nucleus to the cytoplasm so that both the enhancer and DNA molecule are transcribed as part of a functional mRNA transcript in a mammalian cell, introducing the recombinant vector into a mammalian cell, assaying for the nucleocytoplasmic transport of mRNA corresponding to the DNA molecule, and isolating and purifying the sequence having constitutive transport enhancer activity. |