TY - JOUR

T1 - Structural and thermodynamic bases for the design of pure prolactin receptor antagonists: X-ray structure of Del1-9-G129R-hPRL.

AU - Jomain, Jean-Baptiste

AU - Tallet, Estelle

AU - Broutin, Isabelle

AU - Hoos, Sylviane

AU - van Agthoven, Jan

AU - Ducruix, Arnaud

AU - Kelly, Paul A

AU - Kragelund, Birthe B

AU - England, Patrick

AU - Goffin, Vincent

N1 - Keywords: Amino Acid Sequence; Animals; Cell Line; Circular Dichroism; Crystallography, X-Ray; Drug Design; Glycine; Heat; Humans; Kinetics; Models, Molecular; Molecular Sequence Data; Mutation; Prolactin; Protein Binding; Protein Denaturation; Protein Structure, Tertiary; Rats; Receptors, Prolactin; Structural Homology, Protein; Thermodynamics

PY - 2007

Y1 - 2007

N2 - Competitive antagonists of the human prolactin (hPRL) receptor are a novel class of molecules of potential therapeutic interest in the context of cancer. We recently developed the pure antagonist Del1-9-G129R-hPRL by deleting the nine N-terminal residues of G129R-hPRL, a first generation partial antagonist. We determined the crystallographic structure of Del1-9-G129R-hPRL, which revealed no major change compared with wild type hPRL, indicating that its pure antagonistic properties are intrinsically due to the mutations. To decipher the molecular bases of pure antagonism, we compared the biological, physicochemical, and structural properties of numerous hPRL variants harboring N-terminal or Gly(129) mutations, alone or combined. The pure versus partial antagonistic properties of the multiple hPRL variants could not be correlated to differences in their affinities toward the hPRL receptor, especially at site 2 as determined by surface plasmon resonance. On the contrary, residual agonism of the hPRL variants was found to be inversely correlated to their thermodynamic stability, which was altered by all the Gly(129) mutations but not by those involving the N terminus. We therefore propose that residual agonism can be abolished either by further disrupting hormone site 2-receptor contacts by N-terminal deletion, as in Del1-9-G129R-hPRL, or by stabilizing hPRL and constraining its intrinsic flexibility, as in G129V-hPRL. Udgivelsesdato: 2007-Nov-9

AB - Competitive antagonists of the human prolactin (hPRL) receptor are a novel class of molecules of potential therapeutic interest in the context of cancer. We recently developed the pure antagonist Del1-9-G129R-hPRL by deleting the nine N-terminal residues of G129R-hPRL, a first generation partial antagonist. We determined the crystallographic structure of Del1-9-G129R-hPRL, which revealed no major change compared with wild type hPRL, indicating that its pure antagonistic properties are intrinsically due to the mutations. To decipher the molecular bases of pure antagonism, we compared the biological, physicochemical, and structural properties of numerous hPRL variants harboring N-terminal or Gly(129) mutations, alone or combined. The pure versus partial antagonistic properties of the multiple hPRL variants could not be correlated to differences in their affinities toward the hPRL receptor, especially at site 2 as determined by surface plasmon resonance. On the contrary, residual agonism of the hPRL variants was found to be inversely correlated to their thermodynamic stability, which was altered by all the Gly(129) mutations but not by those involving the N terminus. We therefore propose that residual agonism can be abolished either by further disrupting hormone site 2-receptor contacts by N-terminal deletion, as in Del1-9-G129R-hPRL, or by stabilizing hPRL and constraining its intrinsic flexibility, as in G129V-hPRL. Udgivelsesdato: 2007-Nov-9

U2 - 10.1074/jbc.M704364200

DO - 10.1074/jbc.M704364200

M3 - Journal article

C2 - 17785459

VL - 282

SP - 33118

EP - 33131

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

SN - 0021-9258

IS - 45

ER -