Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
48
pubmed:dateCreated
2001-1-5
pubmed:abstractText
To elucidate the molecular basis for the interaction of ligands with the human melanocortin-4 receptor (hMC4R), agonist structure-activity studies and receptor point mutagenesis were performed. Structure-activity studies of [Nle(4), D-Phe(7)]-alpha-melanocyte stimulating hormone (NDP-MSH) identified D-Phe7-Arg8-Trp9 as the minimal NDP-MSH fragment that possesses full agonist efficacy at the hMC4R. In an effort to identify receptor residues that might interact with amino acids in this tripeptide sequence 24 hMC4R transmembrane (TM) residues were mutated (the rationale for choosing specific receptor residues for mutation is outlined in the Results section). Mutation of TM3 residues D122 and D126 and TM6 residues F261 and H264 decreased the binding affinity of NDP-MSH 5-fold or greater, thereby identifying these receptor residues as sites potentially involved in the sought after ligand-receptor interactions. By examination of the binding affinities and potencies of substituted NDP-MSH peptides at receptor mutants, evidence was found that core melanocortin peptide residue Arg8 interacts at a molecular level with hMC4R TM3 residue D122. TM3 mutations were also observed to decrease the binding of hMC4R antagonists. Notably, mutation of TM3 residue D126 to alanine decreased the binding affinity of AGRP (87-132), a C-terminal derivative of the endogenous melanocortin antagonist, 8-fold, and simultaneous mutations D122A/D126A completely abolished AGRP (87-132) binding. In addition, mutation of TM3 residue D122 or D126 decreased the binding affinity of hMC4R antagonist SHU 9119. These results provide further insight into the molecular determinants of hMC4R ligand binding.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Agouti-Related Protein, http://linkedlifedata.com/resource/pubmed/chemical/Amino Acids, Cyclic, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine, http://linkedlifedata.com/resource/pubmed/chemical/Intercellular Signaling Peptides..., http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/MSH, 4-Nle-7-Phe-alpha-, http://linkedlifedata.com/resource/pubmed/chemical/Peptide Fragments, http://linkedlifedata.com/resource/pubmed/chemical/Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Melanocortin, Type 4, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Peptide, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Threonine, http://linkedlifedata.com/resource/pubmed/chemical/alpha-MSH
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
14900-11
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:11101306-Agouti-Related Protein, pubmed-meshheading:11101306-Amino Acid Sequence, pubmed-meshheading:11101306-Amino Acids, Cyclic, pubmed-meshheading:11101306-Binding Sites, pubmed-meshheading:11101306-Cysteine, pubmed-meshheading:11101306-Humans, pubmed-meshheading:11101306-Intercellular Signaling Peptides and Proteins, pubmed-meshheading:11101306-Ligands, pubmed-meshheading:11101306-Models, Molecular, pubmed-meshheading:11101306-Molecular Sequence Data, pubmed-meshheading:11101306-Mutagenesis, Site-Directed, pubmed-meshheading:11101306-Peptide Fragments, pubmed-meshheading:11101306-Protein Binding, pubmed-meshheading:11101306-Protein Conformation, pubmed-meshheading:11101306-Proteins, pubmed-meshheading:11101306-Receptor, Melanocortin, Type 4, pubmed-meshheading:11101306-Receptors, Peptide, pubmed-meshheading:11101306-Recombinant Proteins, pubmed-meshheading:11101306-Threonine, pubmed-meshheading:11101306-alpha-MSH
pubmed:year
2000
pubmed:articleTitle
Molecular determinants of ligand binding to the human melanocortin-4 receptor.
pubmed:affiliation
Departments of General Surgery and Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't