Related Experiment Video
Updated: Apr 27, 2026
Analysis of Transforming Growth Factor ß Family Cleavage Products Secreted Into the Blastocoele of Xenopus laevis Embryos
Published on: July 21, 2021
Identification and mutagenesis of the TACE and γ-secretase cleavage sites in the colony-stimulating factor 1 receptor
Arrash Vahidi1, Gary Glenn1, Peter van der Geer1
1Department of Chemistry and Biochemistry, San Diego State University, 5500 Campanile Dr., San Diego, CA 92182-1030, USA.
Abstract:
Stimulation of macrophages with phorbolesters, bacterial DNA, or lipopolysaccharides causes regulated intramembrane proteolysis or RIPping of the CSF-1 receptor. This process involves TACE-mediated cleavage in the extracellular domain, followed by γ-secretase-mediated cleavage within the transmembrane region. In the current study, we have identified the TACE cleavage site, which is present twelve residues from the carboxy-terminal end of the extracellular domain. Replacement of fourteen residues at the end of the extracellular domain blocked TACE cleavage. In addition, we identified the γ-secretase cleavage site, which is present four residues from the carboxy-terminal end of the transmembrane region. Replacement of six residues surrounding this site strongly reduced intramembrane cleavage. Our results provide new insights into the molecular physiology of the CSF-1 receptor and contribute to our understanding of substrate selection by TACE and γ-secretase.
Insights
Researchers identified specific cleavage sites on the colony-stimulating factor-1 (CSF-1) receptor during regulated intramembrane proteolysis (RIPping). This discovery enhances understanding of CSF-1 receptor processing and protease substrate selection.
Area of Science:
- Molecular and Cellular Biology
- Biochemistry
- Signal Transduction
Background:
- Colony-stimulating factor-1 (CSF-1) receptor undergoes regulated intramembrane proteolysis (RIPping) upon stimulation of macrophages.
- This process involves sequential cleavage by TACE (TNF-α converting enzyme) and γ-secretase.
- The precise cleavage sites and their molecular determinants remain largely uncharacterized.
Purpose of the Study:
- To identify the specific TACE and γ-secretase cleavage sites within the CSF-1 receptor.
- To investigate the impact of mutations at these sites on intramembrane proteolysis.
- To elucidate the molecular mechanisms governing CSF-1 receptor processing.
Main Methods:
- Site-directed mutagenesis was employed to replace specific residues in the CSF-1 receptor.
- Analysis of TACE and γ-secretase cleavage was performed using engineered receptor variants.
- Functional assays were used to assess the consequences of altered cleavage on receptor processing.
Main Results:
- The TACE cleavage site was mapped to twelve residues from the extracellular domain's C-terminus.
- Mutating fourteen residues at the extracellular C-terminus abolished TACE-mediated cleavage.
- The γ-secretase cleavage site was identified four residues from the transmembrane region's C-terminus, with mutations reducing cleavage.
Conclusions:
- This study precisely defines the TACE and γ-secretase cleavage sites in the CSF-1 receptor.
- The findings provide critical insights into the molecular basis of CSF-1 receptor RIPping.
- Results contribute to a deeper understanding of substrate specificity for TACE and γ-secretase.
More Related Videos
11:57Saccharomyces cerevisiae Models of Alzheimer's Disease to Screen Genes, Mutations, and Chemicals Affecting Amyloid Beta Production by γ-Secretase
Published on: June 24, 2025
12:49Mutagenesis and Analysis of Genetic Mutations in the GC-rich KISS1 Receptor Sequence Identified in Humans with Reproductive Disorders
Published on: September 4, 2011
