Human monocyte chemoattractant protein‐1 (MCP‐1) Full‐length cDNA cloning, expression in mitogen‐stimulated blood mononuclear leukocytes, and sequence similarity to mouse competence gene JE

Abstract
The purpose of this work was to analyze cDNA encoding human monocyte chemoattractant protein‐1 (MCP‐1), previously isolated from glioma cell line culture fluid. Screening of a cDNA library from total poly(A) RNA of glioma cell line U‐105MG yielded a clone that coded for the entire MCP‐1. Nucleotide sequence analysis and comparison with the amino acid sequence of purified MCP‐1 showed that the cDNA clone comprises a 53‐nucleotide 5′‐non‐coding region, an open reading frame coding for a 99‐residue protein of which the last 76 residues correspond exactly to pure MCP‐1, and a 389‐nucleotide 3′‐untranslated region. The hydrophobicity of the first 23 residues is typical of a signal peptide. Southern blot analysis of human and animal genomic DNA showed that there is a single MCP‐1 gene, which is conserved in several primates. MCP‐1 mRNA was induced in human peripheral blood mononuclear leukocytes (PBMNLs) by PHA, LPS and IL‐1, but not by IL‐2, TNF, or IFN‐γ. Among proteins with similar sequences, the coding regions of MCP‐1 and mouse JE show 68% identity. This suggests that MCP‐1 is the human homologue of the mouse competence gene JE.