Melanocortin receptor ligand selectivity has been a question not easily answered. The inability to functionally express melanocortin 2 receptor (MC2R) has inhibited the study of why MC2R is only stimulated by ACTH, a melanocortin hormone. With the recent discovery of the MC2R accessory protein (MRAP), creating a heterologous system is now feasible. Using a general cell line like CHO-K1 cells, which do not express endogenous MCRs, we were able to create a heterologous expression system and test the selectivity of MC2R using analog variants of ACTH(1-24). Our results indicate an amino acid requirement in the C-terminal portion of ACTH(1-24) for activation, which supports the 2-step method of activation hypothesized for MC2R. This site, the tetra basic cleavage site, when altered does not stimulate cAMP production and does not compete with ACTH(1-24) for binding. We also demonstrate the potential for a non-mammalian MC2R system in cloning full length Silurana tropicalis MC2R and completed localization studies with this system with MRAP using CHO-K1 cells.
","abstract_html":"<p>Melanocortin receptor ligand selectivity has been a question not easily answered. The inability to functionally express melanocortin 2 receptor (MC2R) has inhibited the study of why MC2R is only stimulated by ACTH, a melanocortin hormone. With the recent discovery of the MC2R accessory protein (MRAP), creating a heterologous system is now feasible. Using a general cell line like CHO-K1 cells, which do not express endogenous MCRs, we were able to create a heterologous expression system and test the selectivity of MC2R using analog variants of ACTH(1-24). Our results indicate an amino acid requirement in the C-terminal portion of ACTH(1-24) for activation, which supports the 2-step method of activation hypothesized for MC2R. This site, the tetra basic cleavage site, when altered does not stimulate cAMP production and does not compete with ACTH(1-24) for binding. We also demonstrate the potential for a non-mammalian MC2R system in cloning full length <em>Silurana tropicalis</em> MC2R and completed localization studies with this system with MRAP using CHO-K1 cells.</p>","abstract_has_math":false,"creators":["Veo, Kristopher D."],"institution":null,"degree_name":"M.S.","degree_level":"Masters Thesis","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Robert M. Dores, Ph.D.","Cynthia V. Fukami","Joseph Angleson","Scott Barbee"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-01-01T08:00:00Z","date_published":"2009-01-01T08:00:00Z","updated_at":"2026-07-24T02:03:19Z","subjects":["ACTH","Adrenocorticotropic hormone","Activation","CHO-K1","MC2R","Melanocortin 2 receptor","Melanocortin","Silurana Tropicalis","Biology","Molecular Biology"],"languages":["en"],"rights":["Copyright is held by the author. User is responsible for all copyright compliance.
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"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Amino Acid Residues Implicated in the Interaction of Melanocortin Ligands and Their Receptors: A Study of MC2R Selectivity"]}]}],"canonical_facts":{"dc:contributor":["Robert M. Dores, Ph.D.","Cynthia V. Fukami","Joseph Angleson","Scott Barbee"],"dc:creator":["Veo, Kristopher D."],"dc:date.available":["2001-01-01T08:00:00Z"],"dc:description.abstract":["Melanocortin receptor ligand selectivity has been a question not easily answered. The inability to functionally express melanocortin 2 receptor (MC2R) has inhibited the study of why MC2R is only stimulated by ACTH, a melanocortin hormone. With the recent discovery of the MC2R accessory protein (MRAP), creating a heterologous system is now feasible. Using a general cell line like CHO-K1 cells, which do not express endogenous MCRs, we were able to create a heterologous expression system and test the selectivity of MC2R using analog variants of ACTH(1-24). Our results indicate an amino acid requirement in the C-terminal portion of ACTH(1-24) for activation, which supports the 2-step method of activation hypothesized for MC2R. This site, the tetra basic cleavage site, when altered does not stimulate cAMP production and does not compete with ACTH(1-24) for binding. We also demonstrate the potential for a non-mammalian MC2R system in cloning full length Silurana tropicalis MC2R and completed localization studies with this system with MRAP using CHO-K1 cells.
"],"dc:format":["application/pdf"],"dc:identifier":["https://digitalcommons.du.edu/etd/945"],"dc:language":["en"],"dc:rights":["Copyright is held by the author. User is responsible for all copyright compliance.
"],"dc:subject":["ACTH","Adrenocorticotropic hormone","Activation","CHO-K1","MC2R","Melanocortin 2 receptor","Melanocortin","Silurana Tropicalis","Biology","Molecular Biology"],"dc:title":["Amino Acid Residues Implicated in the Interaction of Melanocortin Ligands and Their Receptors: A Study of MC2R Selectivity"],"thesis:degree_level":["Masters Thesis"],"thesis:degree_name":["M.S."]},"updated_at":"2026-07-24T02:03:19Z"}