Regulation of human LZIP expression by NF-kappaB and its involvement in monocyte cell migration induced by Lkn-1

J Biol Chem. 2007 Apr 13;282(15):11092-100. doi: 10.1074/jbc.M607962200. Epub 2007 Feb 12.

Abstract

Human LZIP is a transcription factor that is involved in leukocyte cell mobility. Expression of LZIP is known to differentially regulate monocyte cell migration induced by CCR1-dependent chemokines. However, its transcriptional regulation has not been characterized. Our results indicate that Lkn-1 induces LZIP expression in a time- and dose-dependent manner, and the induction of LZIP shows an immediate early response to Lkn-1. We identified and cloned approximately 1.4 kb of the LZIP promoter from a human genomic DNA. To identify regulatory elements controlling restricted expression of LZIP, deletion mutants were constructed from the 1469-bp LZIP promoter region (-1219/+251) linked to the luciferase reporter gene. Maximal promoter activity was contained within 613 bp from the tentative transcription initiation site and was sharply reduced in a truncated construct (-338/+251). This promoter sequence contained consensus NF-kappaB- and Sp-1-binding sites. Results from an inhibitor assay showed that NF-kappaB is involved in Lkn-1-induced LZIP expression, but Sp-1 is not. We also demonstrated that NF-kappaB binds to the LZIP promoter and that the binding is specific, as revealed by an electrophoretic mobility shift assay and a mutation analysis. Chemotaxis analysis showed that LZIP expression because of the NF-kappaB subfamily is specifically involved in Lkn-1-induced chemotaxis. Our findings suggest that transcription factor NF-kappaB plays an important role in regulation of LZIP expression, and LZIP expression regulates the monocyte cell migration induced by Lkn-1.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Cell Line
  • Chemokines / metabolism
  • Chemokines, CC / genetics
  • Chemokines, CC / metabolism*
  • Chemotaxis*
  • Cyclic AMP Response Element-Binding Protein / metabolism*
  • Gene Deletion
  • Humans
  • Macrophage Inflammatory Proteins
  • Molecular Sequence Data
  • Monocytes / cytology*
  • Monocytes / metabolism*
  • Monokines / genetics
  • Monokines / metabolism*
  • Mutation / genetics
  • NF-kappa B / metabolism*
  • Promoter Regions, Genetic / genetics
  • Protein Binding
  • Protein Subunits / metabolism
  • Receptors, CCR1
  • Receptors, Chemokine / metabolism
  • Time Factors
  • Transcriptional Activation / genetics

Substances

  • CCL15 protein, human
  • CCR1 protein, human
  • CREB3 protein, human
  • Chemokines
  • Chemokines, CC
  • Cyclic AMP Response Element-Binding Protein
  • Macrophage Inflammatory Proteins
  • Monokines
  • NF-kappa B
  • Protein Subunits
  • Receptors, CCR1
  • Receptors, Chemokine