REGULATION OF NF-KAPPA-B, AP-1, NFAT, AND STAT1 NUCLEAR IMPORT IN T-LYMPHOCYTES BY NONINVASIVE DELIVERY OF PEPTIDE CARRYING THE NUCLEAR-LOCALIZATION SEQUENCE OF NF-KAPPA-B P50

Activation of T lymphocytes by Ags or cytokines results in translocati on of the transcription factors NF-kappa B, AP-1, NFAT, and STAT from the cytoplasm into the nucleus, The first step in the nuclear import p rocess is recognition of a nuclear localization sequence (NLS) within the karyophilic protein by a cytoplasmic receptor such as the importin (karyopherin)-alpha subunit, The NLSs of NF-kappa B, AP-1, and NFAT d iffer and the NLS of STAT1 has not yet been identified, Herein we demo nstrate that the inducible nuclear import of NF-kappa B, AP-1, NFAT, a nd STAT1 in Jurkat T lymphocytes is significantly inhibited by a cell- permeable peptide carrying the NLS of the NF-kappa B p50 subunit, NLS peptide-mediated disruption of the nuclear import of these transcripti on factors results in inhibition of I kappa B alpha and IL-2 gene expr ession, processes dependent on NF-kappa B or the combination of NF-kap pa B, AP-1, and NFAT, Further, we show that inhibitory NLS peptide int eracts in vitro with a cytoplasmic NLS receptor complex comprised of t he Rch1/importin (karyopherin)-beta heterodimer expressed in Jurkat T cells, Taken together, these data indicate that the inducible nuclear import of NF-kappa B, AP-1, NFAT, and STAT1 in Jurkat T cells can be r egulated by NLS peptide delivered noninvasively to the cytoplasm of Ju rkat T cells to target members of the importin (karyopherin)-alpha bet a NLS receptor complex.