This Article Full Text Full Text (PDF) All Versions of this Article: 18/6/1499    most recent Author Manuscript (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fanelli, F. Articles by Themmen, A. P. N. Search for Related Content PubMed PubMed Citation Articles by Fanelli, F. Articles by Themmen, A. P. N.

Insight into Mutation-Induced Activation of the Luteinizing Hormone Receptor: Molecular Simulations Predict the Functional Behavior of Engineered Mutants at M398

Dulbecco Telethon Institute and Department of Chemistry (F.F.), University of Modena and Reggio Emilia, 4100 Modena, Italy; and Department of Internal Medicine (M.V.-P., M.T., A.Z., J.W.M.M., A.P.N.T.), Erasmus MC, 3000 DR Rotterdam, The Netherlands

Address all correspondence and requests for reprints to: Francesca Fanelli, Dulbecco Telethon Institute and Department of Chemistry, University of Modena and Reggio Emilia, Via Campi 183, 41100 Modena, Italy. E-mail: fanelli{at}unimo.it.

In this study, molecular simulations have been combined with site-directed mutagenesis experiments to explore M398(2.43), a LH (lutropin) receptor (LHR) site in helix 2 susceptible to spontaneous activating mutations, and to develop a computational tool for predicting the functionality (i.e. active or nonactive) of LHR mutants.

Site-directed mutagenesis experiments engineered 15 different substitutions for M389(2.43), which resulted in variable levels of constitutive activity, inversely correlated with the size of the replacing amino acid. This inverse correlation is suggested to be mediated by I460(3.46), M571(6.37), and Y623(7.53), the tyrosine of the NPxxY motif. In fact, size reduction at position 398(2.43), which is concurrent with constitutive receptor activity, releases the van der Waals interactions found in the wild-type LHR between M398(2.43) and these three amino acids, resulting in structural modifications in the proximity to the E/DRY/W motif. An increment, above a threshold value, in the solvent accessibility of the cytosolic ends of helices 3 and 6 is the main structural feature shared by the active mutants of the LHR. This feature has been successfully used for predicting the functionality of the engineered mutants at M398(2.43), proving that molecular simulations can be useful for in silico screening of LHR mutants.

This article has been cited by other articles:

				X. Feng, T. Muller, D. Mizrachi, F. Fanelli, and D. L. Segaloff An Intracellular Loop (IL2) Residue Confers Different Basal Constitutive Activities to the Human Lutropin Receptor and Human Thyrotropin Receptor through Structural Communication between IL2 and Helix 6, via Helix 3 Endocrinology, April 1, 2008; 149(4): 1705 - 1717. [Abstract] [Full Text] [PDF]

				K. Angelova, F. Fanelli, and D. Puett Contributions of Intracellular Loops 2 and 3 of the Lutropin Receptor in Gs Coupling Mol. Endocrinol., January 1, 2008; 22(1): 126 - 138. [Abstract] [Full Text] [PDF]

				M. Zhang, Y.-X. Tao, G. L. Ryan, X. Feng, F. Fanelli, and D. L. Segaloff Intrinsic Differences in the Response of the Human Lutropin Receptor Versus the Human Follitropin Receptor to Activating Mutations J. Biol. Chem., August 31, 2007; 282(35): 25527 - 25539. [Abstract] [Full Text] [PDF]

				G. Kleinau, M. Brehm, U. Wiedemann, D. Labudde, U. Leser, and G. Krause Implications for Molecular Mechanisms of Glycoprotein Hormone Receptors Using a New Sequence-Structure-Function Analysis Resource Mol. Endocrinol., February 1, 2007; 21(2): 574 - 580. [Abstract] [Full Text] [PDF]

				J. Van Durme, F. Horn, S. Costagliola, G. Vriend, and G. Vassart GRIS: Glycoprotein-Hormone Receptor Information System Mol. Endocrinol., September 1, 2006; 20(9): 2247 - 2255. [Abstract] [Full Text] [PDF]

				U. Ringkananont, J. Van Durme, L. Montanelli, F. Ugrasbul, Y. M. Yu, R. E. Weiss, S. Refetoff, and H. Grasberger Repulsive Separation of the Cytoplasmic Ends of Transmembrane Helices 3 and 6 Is Linked to Receptor Activation in a Novel Thyrotropin Receptor Mutant (M626I) Mol. Endocrinol., April 1, 2006; 20(4): 893 - 903. [Abstract] [Full Text] [PDF]

				D. Piersma, E. M. J. J. Berns, M. Verhoef-Post, A. G. Uitterlinden, I. Braakman, H. A. P. Pols, and A. P. N. Themmen A Common Polymorphism Renders the Luteinizing Hormone Receptor Protein More Active by Improving Signal Peptide Function and Predicts Adverse Outcome in Breast Cancer Patients J. Clin. Endocrinol. Metab., April 1, 2006; 91(4): 1470 - 1476. [Abstract] [Full Text] [PDF]

				M. Zhang, D. Mizrachi, F. Fanelli, and D. L. Segaloff The Formation of a Salt Bridge Between Helices 3 and 6 Is Responsible for the Constitutive Activity and Lack of Hormone Responsiveness of the Naturally Occurring L457R Mutation of the Human Lutropin Receptor J. Biol. Chem., July 15, 2005; 280(28): 26169 - 26176. [Abstract] [Full Text] [PDF]