HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Hu, R. Articles by Zoon, K. Search for Related Content PubMed PubMed Citation Articles by Hu, R. Articles by Zoon, K.

Human IFN- Protein Engineering: The Amino Acid Residues at Positions 86 and 90 Are Important for Antiproliferative Activity¹

Renqiu Hu^2,*, Joseph Bekisz^*, Hana Schmeisser^*, Peter McPhie and Kathryn Zoon^*

^* Division of Therapeutic Proteins, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892; and National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892

Human IFN- is a family of structurally related proteins that exhibit a wide range of antiproliferative activities. To understand the structural basis for these different antiproliferative activities, eight recombinant human IFN- hybrids (HY) of 21a/2c (HY-4, HY-5) and mutants (site-directed mutagenesis (SDM)-1, 2 and cassette mutagenesis (CM)-1, 2, 3, and 4) have been expressed, purified, and characterized. The data showed that the amino acid region 81–95 is important for antiproliferative activity. Site-directed mutagenesis and cassette mutagenesis studies showed that if serine (S) 86 and asparagine (N) 90 were replaced by tyrosine (Y), the antiproliferative activity was increased. We have also observed that if Y86 was replaced by isoleucine (I), the antiproliferative activity was comparable. However, if Y86 was replaced by aspartic acid (D), lysine (K), or alanine (A), the antiproliferative activity was substantially decreased. Our results indicate that Y and/or I at position 86 and Y at position 90 are very important in antiproliferative activity of human IFN-. Circular dichroism spectra showed that the amino acid replacements at position 86 did not change the secondary structure. Thus the biological activity changes among those mutants do not appear to be due to conformational changes. The results also suggest that hydrophobic residue(s) at position 86 may be important for the interaction of the molecule with its receptor. The competitive binding data correlated with the antiproliferative activity. The N-terminal region of the molecule and the hydrophobic residues (including Y and I) on the C-helix region at positions 86 and/or 90 are important for binding and antiproliferative activities of human IFN-s.

This article has been cited by other articles:

				T. Matsumiya, S. M. Prescott, and D. M. Stafforini IFN-{epsilon} Mediates TNF-{alpha}-Induced STAT1 Phosphorylation and Induction of Retinoic Acid-Inducible Gene-I in Human Cervical Cancer Cells J. Immunol., October 1, 2007; 179(7): 4542 - 4549. [Abstract] [Full Text] [PDF]

				D. A. Jaitin, L. C. Roisman, E. Jaks, M. Gavutis, J. Piehler, J. Van der Heyden, G. Uze, and G. Schreiber Inquiring into the Differential Action of Interferons (IFNs): an IFN-{alpha}2 Mutant with Enhanced Affinity to IFNAR1 Is Functionally Similar to IFN-{beta}. Mol. Cell. Biol., March 1, 2006; 26(5): 1888 - 1897. [Abstract] [Full Text] [PDF]

				M. J. Grace, S. Lee, S. Bradshaw, J. Chapman, J. Spond, S. Cox, M. DeLorenzo, D. Brassard, D. Wylie, S. Cannon-Carlson, et al. Site of Pegylation and Polyethylene Glycol Molecule Size Attenuate Interferon-{alpha} Antiviral and Antiproliferative Activities through the JAK/STAT Signaling Pathway J. Biol. Chem., February 25, 2005; 280(8): 6327 - 6336. [Abstract] [Full Text] [PDF]