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A RAPID Method for Blood Processing to Increase the Yield of Plasma Peptide Levels in Human Blood
Published on: April 28, 2016
On the processing of proghrelin to ghrelin
Xiaorong Zhu1, Yun Cao, Keith Voogd
1Department of Biochemistry and Molecular Biology and Howard Hughes Medical Institute, The University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
The Journal of Biological Chemistry
|October 20, 2006
Summary
Researchers identified prohormone convertase 1/3 (PC1/3) as key in processing ghrelin from its precursor. Acylation is independent of this processing, and precursor levels rise when PC1/3 is absent.
Area of Science:
- Endocrinology
- Molecular Biology
- Biochemistry
Background:
- Ghrelin, an orexigenic hormone, regulates appetite and energy homeostasis.
- Its biosynthesis and acylation mechanisms remain incompletely understood.
- Previous research focused on ghrelin's physiological effects, leaving gaps in knowledge regarding its production pathway.
Purpose of the Study:
- To elucidate the endoproteolytic processing of ghrelin from its precursor, proghrelin.
- To identify the specific prohormone convertase responsible for this conversion.
- To investigate the relationship between ghrelin acylation and its processing, and the impact of processing deficiency on precursor mRNA expression.
Main Methods:
- Utilized prohormone convertase null mouse strains generated in-house.
- Employed Western blotting, mass spectrometry, and immunocytochemical techniques.
- Analyzed endoproteolytic processing, peptide acylation, and proghrelin mRNA expression.
Main Results:
- Prohormone convertase 1/3 (PC1/3) was identified as the primary endoprotease responsible for converting proghrelin to mature ghrelin in mouse stomach.
- Ghrelin acylation was demonstrated to be independent of the processing pathway.
- Proghrelin mRNA expression was significantly increased in mice lacking PC1/3 (processing-deficient).
Conclusions:
- PC1/3 is essential for the endoproteolytic processing of proghrelin into ghrelin.
- Ghrelin acylation occurs independently of PC1/3-mediated processing.
- PC1/3 deficiency leads to compensatory upregulation of proghrelin mRNA.
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