Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
5
|
| pubmed:dateCreated |
1997-3-20
|
| pubmed:abstractText |
The C-terminal region of interleukin-5 has previously been suggested to be important for biological activity [Mackenzie et al., (1991), Mol. Immunol. 28, 155-158; Kodama et al. (1991), Biochem. Biophys. Res. Commun. 178, 514-519]. We have investigated this region by making a series of truncation mutants. The proteins were expressed in Escherichia coli, purified from inclusion bodies, and were able to refold with the disulfide homodimeric topology typical of interleukin-5. Analysis of the truncated carboxy-terminal proteins in an interleukin-5-dependent proliferation assay on TF-1 cells showed a rapid loss of activity as the C-terminal was shortened by more than two amino acids. This loss of biological activity correlated with a drop in binding affinity to both the alpha chain of the receptor and the high-affinity complex consisting of the alpha and beta subunits. Analysis of the proteins by 1H-NMR showed that the truncated mutants have higher exchange rates with solvent, indicating a less rigid structure. The carboxy-terminal region is therefore necessary to maintain the stability of the four-helix bundle and to orient correctly the important residues of the fourth helix. Inspection of the structure determined by X-ray crystallography shows that Trp-110 acts as the major residue in anchoring the fourth helix.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Jul
|
| pubmed:issn |
0277-8033
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
15
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
491-9
|
| pubmed:dateRevised |
2004-11-17
|
| pubmed:meshHeading |
pubmed-meshheading:8895095-Amino Acid Sequence,
pubmed-meshheading:8895095-Cell Division,
pubmed-meshheading:8895095-Crystallography, X-Ray,
pubmed-meshheading:8895095-Dimerization,
pubmed-meshheading:8895095-Escherichia coli,
pubmed-meshheading:8895095-Humans,
pubmed-meshheading:8895095-Interleukin-5,
pubmed-meshheading:8895095-Magnetic Resonance Spectroscopy,
pubmed-meshheading:8895095-Mutagenesis, Site-Directed,
pubmed-meshheading:8895095-Protein Structure, Tertiary,
pubmed-meshheading:8895095-Receptors, Interleukin,
pubmed-meshheading:8895095-Recombinant Proteins,
pubmed-meshheading:8895095-Sequence Deletion,
pubmed-meshheading:8895095-Structure-Activity Relationship,
pubmed-meshheading:8895095-Tumor Cells, Cultured
|
| pubmed:year |
1996
|
| pubmed:articleTitle |
The carboxy-terminal region of human interleukin-5 is essential for maintenance of tertiary structure but not for dimerization.
|
| pubmed:affiliation |
Glaxo Institute for Molecular Biology, Geneva, Switzerland.
|
| pubmed:publicationType |
Journal Article
|