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, Activation, CHO-K1, MC2R, 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.

Comments

Copyright is held by the author.

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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