Abstract
Human leucine zipper protein (LZIP) associates with CC chemokine receptor 1 (CCR1) and this protein-protein interaction should play an important role in leukocyte cell mobility. LZIP is known to regulate leukotactin-1 (Lkn-1)-dependent cell migration without affecting the chemotactic activities of other CC chemokines that bind to CCR1. Since Lkn-1 is engaged in the transcriptional activation of nuclear factor κB(NF-κB) and subsequent activation of the chemoattractant ability of leukocytes, we investigated the regulatory role of LZIP in the NF-κB pathway that is induced by CCR1-dependent chemokines. LZIP increased NF-κB-dependent luciferase activity in response to Lkn-1 in HOS/CCR1 cells and THP-1 cells. However, the NF-κB-dependent luciferase activities induced by other CCR1-dependent chemokines were not affected by LZIP overexpression. LZIP also increased Lkn-1-induced chemotactic activity through activation of the NF-κB pathway, whereas LZIP did not affect either the transactivation of NF-κB or the chemotactic activities induced by other CCR1-dependent chemokines. Western blot analysis showed that LZIP increased the degradation of IκBα induced by Lkn-1 but not by other CCR1-dependent chemokines. Results from electrophoretic mobility shift assay (EMSA) showed that LZIP enhanced the Lkn-1-induced DNA-binding activity of NF-κB. These data indicate that LZIP functions as a positive regulator in the NF-κB activation pathway that is triggered by Lkn-1 without affecting the transcriptional activation of NF-κB induced by other CCR1-dependent chemokines.
Original language | English |
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Pages (from-to) | 630-637 |
Number of pages | 8 |
Journal | Journal of Cellular Physiology |
Volume | 211 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2007 Jun |
ASJC Scopus subject areas
- Physiology
- Clinical Biochemistry
- Cell Biology