5-Lipoxygenase compartmentalization in granulocytic cells is modulated by an internal bipartite nuclear localizing...

A region of basic amino acids spanning residues 639-656 in the human 5-lipoxygenase sequence resembles a consensus bipartite nuclear localizing sequence. A synthetic peptide consisting of the Kaposi fibroblast growth factor signal sequence fused to the 5-lipoxygenase639-656 bipartite nuclear localizing sequence has a prominent inhibitory effect on 5-lipoxygenase catalysis in granulocytic HL-60 cells activated by calcium ionophor A23187. Recombinant 5-lipoxygenase was not affected by the peptide. The peptide also inhibited redistribution of 5-lipoxygenase from the cytosol to the nuclear membrane of HL-60 cells stimulated by A23187. 5-Lipoxygenase protein was detected in nuclear factor kappaB (NF-kappaB) p65 subunit immunoprecipitate fractions prepared from HL-60 cell lysates. The amount of 5-lipoxygenase protein coimmunoprecipitated by NF-kappaB antiserum was increased following A23187 stimulation. In cells treated with agents that block 5-lipoxygenase translocation to the nucleus, 5-lipoxygenase protein appearing in the NF-kappaB immunoprecipitate was diminished. Our results implicate an internal bipartite nuclear localizing sequence as a regulatory domain that modulates 5-lipoxygenase redistribution and catalysis in granulocytic cells. Additionally, our results suggest that molecular determinants which govern 5-lipoxygenase and NF-kappaB redistribution to the nucleus may be coordinately controlled in granulocytic cells.