TY  - JOUR
A1  - Müller, T.
A1  - Dieckmann, T.
A1  - Sebald, Walter
A1  - Oschkinat, H.
T1  - Aspects of receptor binding and signalling of interleukin-4 investigated by site-directed mutagenesis and NMR spectroscopy
N2  - Cytokines are hormones that carry information from ceJI to ceH. This information is read from their surface upon binding to transmembrane receptors and by the subsequent initiation of receptor oligomerization. An inftuence on this process through mutagenesis on the hormone surface is highly desirab)e for medical reasons. However, an understanding of hormone-receptor interactions requires insight into the structural changes introduced by the mutations. In this line structural studies on human TL-4 and the medically important IL-4 antagonists YI24D and Y124G are presented. The site a.round YI24 is an important epitope responsible for the a.bility of 11-4 t.o ca.use a signal in the target cells. It is shown that the local main-chain structure around residue 124 in the variants remains unchanged. A strategy is presented here which allows the study of these types of proteins and their variants by NMR which does not require carbon Iabeiied sa.mples.
KW  - Biochemie
KW  - Interleukin-4
KW  - protein structure
KW  - NMR
KW  - signal transduction
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62444
ER  - 
TY  - JOUR
A1  - Müller, T.
A1  - Sebald, Walter
A1  - Oschkinat, H.
T1  - Antagonist design through forced electrostatic mismatch
N2  - No abstract available
KW  - Biochemie
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62408
ER  - 
TY  - JOUR
A1  - Demchuk, E.
A1  - Mueller, T.
A1  - Oschkinat, H.
A1  - Sebald, Walter
A1  - Wade, R. C.
T1  - Receptor binding properties of four-helix-bundle growth factors deduced from electrostatic analysis
N2  - Hormones of the hematopoietin class mediate signal transduction by binding to specific transmembrane receptors. Structural data show that the human growth hormone (hGH) forms a complex with a homodimeric receptor and that hGH is a member of a class of hematopoietins possessing an antiparallel 4-a-helix bundle fold. Mutagenesis experiments suggest that electrostatic interactions may have an important influence on hormonereceptor recognition. In order to examine the specificity of hormone-receptor complexation, an analysis was made of the electrostatic potentials of hGH, interleukin-2 (IL-2), interleukin-4 (IL-4), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and the hGH and IL-4 receptors. The binding surfaces of hGH and its receptor, and of IL-4 and its receptor, show complementary electrostatic potentials. The potentials of the hGH and its receptor display approximately 2-fold rotational symmetry because the receptor subunits are identical. In contrast, the potentials of GM-CSF and IL-2 Iack such symmetry, consistent with their known high affinity for hetero-oligomeric receptors. Analysis of the electrostatic potentials supports a recently proposed hetero-oligomeric model for a high-affinity IL-4 receptor and suggests a possible new receptor binding mode for G-CSF; it also provides valuable information for guiding structural and mutagenesis studies of signal-transducing proteins and their receptors.
KW  - Biochemie
KW  - cytokines
KW  - electrostatic potential
KW  - hematopoietic receptors
KW  - human growth factor
KW  - interleukins
KW  - molecular recognition
Y1  - 1994
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-62424
ER  -