Characterization of an extended form of recombinant human insulin-like growth factor II

• Published in: The Journal of biological chemistry Vol. 266; no. 17; pp. 11058 - 11062
• Main Authors: HAMMARBERG, B, TALLY, M, SAMUELSSON, E, WADENSTEN, H, HOLMGREN, E, HARTMANIS, M, HALL, K, UHLEN, M, MOKS, T
• Format: Journal Article
• Language: English
• Published: Bethesda, MD American Society for Biochemistry and Molecular Biology 15.06.1991
• Subjects: Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Base Sequence; Biological and medical sciences; Cell Division - drug effects; Cell Line; Cell Membrane - metabolism; Escherichia coli - genetics; Female; Fundamental and applied biological sciences. Psychology; Genes; Humans; Insulin-Like Growth Factor II - genetics; Insulin-Like Growth Factor II - metabolism; Insulin-Like Growth Factor II - pharmacology; Kinetics; Molecular Sequence Data; Oligonucleotide Probes; Placenta - metabolism; Pregnancy; Protein hormones. Growth factors. Cytokines; Proteins; Radioimmunoassay; Receptors, Cell Surface - metabolism; Receptors, Somatomedin; Recombinant Fusion Proteins - isolation & purification; Recombinant Proteins - metabolism; Recombinant Proteins - pharmacology; Human; Binding capacity; Escherichia coli; Radioimmunoassay; Bacteria; Recombinant protein; Insulin like growth factor 2; Biological activity; Enterobacteriaceae; Growth factor
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)99127-1

To investigate the biological role of variants of human insulin-like growth factor II (IGF-II), an extended form designated IGF-IIE21, with a molecular mass of 9.8 kDa, was produced in Escherichia coli as a stable and soluble secreted fusion protein. After site-specific cleavage of the affinity purified fusion protein, followed by purification using ion exchange and reversed phase chromatography, it could be demonstrated that IGF-IIE21 and IGF-II have similar or identical activities according to radioimmunoassay and radioreceptor assay. However, IGF-IIE21 showed only 1% growth promotion activity as compared with IGF-II in a clonal expansion assay using human K562 cells which lacks IGF-I receptors. These results suggest that this extended variant of IGF-II can bind to the receptor but has limited growth promoting activity.