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Updated: Dec 28, 2025
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Membrane-SPINE: A Biochemical Tool to Identify Protein-protein Interactions of Membrane Proteins In Vivo
Published on: November 7, 2013
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Physiological functions of SPP/SPPL intramembrane proteases.
Torben Mentrup1, Florencia Cabrera-Cabrera1, Regina Fluhrer2,3,4
1Institute for Physiological Chemistry, Medizinisch-Theoretisches Zentrum MTZ, Technische Universität Dresden, Fiedlerstraße 42, 01307, Dresden, Germany.
Cellular and Molecular Life Sciences : CMLS
|February 14, 2020
Summary
Signal peptide peptidase-like (SPPL) proteases cleave transmembrane proteins. Studying SPPL-deficient mice reveals their roles in regulating cell signaling, membrane trafficking, and protein glycosylation.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Intramembrane proteolysis involves cleaving proteins within transmembrane segments.
- Signal peptide peptidase (SPP) and its homologues, the SPP-like (SPPL) proteases (SPPL2a, SPPL2b, SPPL2c, SPPL3), are aspartyl proteases.
- SPP/SPPL proteases share catalytic mechanisms with γ-secretase but cleave type II transmembrane proteins.
Purpose of the Study:
- To review the biological functions and substrate discovery of SPP/SPPL proteases.
- To summarize hypotheses linking SPP/SPPL-deficient mouse model phenotypes to enzyme function.
- To elucidate the role of SPP/SPPL-mediated cleavage in cellular processes.
Main Methods:
- Characterization of SPP/SPPL-deficient mouse models.
- Analysis of substrate discovery for SPP/SPPL proteases.
- Review of current hypotheses on enzyme function and cellular impact.
Main Results:
- SPP/SPPL-deficient mouse models have revealed diverse biological functions.
- These proteases influence multiple cell biological pathways, including signal transduction, membrane trafficking, and protein glycosylation.
- SPP/SPPL-mediated cleavage acts as specific regulatory switches rather than non-specific proteolysis.
Conclusions:
- SPP/SPPL proteases are crucial regulators of cellular processes.
- Understanding their function is key to deciphering complex biological pathways.
- Further research into SPP/SPPL proteases will uncover more substrates and functions.
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