Internal deletions of amino acids 29-42 of human interleukin-6 (IL-6) differentially affect bioactivity and folding

• Published in: FEBS letters 1991-08, Vol.288 (1-2), p.197-200
• Main Authors: Arcone, Rosaria, Fontaine, Veronique, Coto, Iolanda, Content, Jean, Ciliberto, Gennaro
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Analysis of the immune response. Humoral and cellular immunity; Antibodies, Monoclonal; Base Sequence; Binding Sites - genetics; Biological and medical sciences; C-reactive protein; CAT; chloroamphenicol acetyltransferase gene; CRP; CRP/CAT assay; Escherichia coli - metabolism; Fundamental and applied biological sciences. Psychology; Fundamental immunology; HGF; HGF assay; Humans; hybridoma growth factor; IL-6; IL-6 R; Immunobiology; Interleukin-6; Interleukin-6 - chemistry; Interleukin-6 - genetics; interleukin-6 receptor; Internal deletions; IPTG; isopropylthio-galactopyranoside; Lymphokines, interleukins ( function, expression); Molecular Sequence Data; Monoclonal antibody; Mutation - genetics; Peptide Fragments; Precipitin Tests; Protein Conformation; Recombinant Proteins - biosynthesis; Regulatory factors and their cellular receptors; Tumor Cells, Cultured
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(91)81033-5

Internal deletions of the human interleukin-6 (IL-6) cDNA have been generated in the region encoding residues 29 to 42. Mutant proteins were produced by in vitro transcription—translation or in Escherichia coli and tested for their biological activity using the hybridoma growth factor (HGF) assay or a transcriptional activation assay on human hepatoma cells. The folding of the mutants was also checked by immunoprecipitation with conformation-specific monoclonal antibodies. The results show that only residues 29 to 34 are crucial for IL-6 activity and that the first two amino acids are probably involved in the definition of the IL-6 active site.