Date of Award

1-1-2009

Document Type

Thesis

Degree Name

M.S.

Department

Biological Sciences

First Advisor

Robert M. Dores, Ph.D.

Keywords

ACTH, Adrenocorticotropic hormone, Activation, CHO-K1, MC2R, Melanocortin 2 receptor, Melanocortin, Silurana Tropicalis

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.

Publication Statement

Copyright is held by the author. User is responsible for all copyright compliance.

Provenance

Received from ProQuest

Rights holder

Kristopher D. Veo

File size

78 p.

File format

application/pdf

Language

en

Discipline

Molecular Biology

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