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07:17
Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex
Published on: August 2, 2021
Posttranslational regulation of Fas ligand function
Matthias Voss1, Marcus Lettau, Maren Paulsen
1Molecular Immunology, Institute of Immunology, Medical Center Schleswig-Holstein Campus Kiel, Arnold-Heller-Str, 3, Bldg, 17, D-24105 Kiel, Germany. ojanssen@email.uni-kiel.de.
Cell Communication and Signaling : CCS
|December 31, 2008
Summary
Fas ligand (a death factor) regulates immune responses and can be exploited by tumors. Its function is tightly controlled through storage, release, and post-translational modifications, crucial for therapeutic strategies.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- Fas ligand (FasL) is a key mediator of apoptosis, crucial for immune system functions like cytotoxicity and immune response termination.
- FasL expression on tumors can lead to immune evasion by eliminating Fas-positive tumor-infiltrating cells.
- Strict regulation of FasL is essential to prevent uncontrolled cellular damage.
Purpose of the Study:
- To elucidate the intricate regulatory mechanisms governing Fas ligand (FasL) function and its biological roles.
- To understand how FasL is stored, mobilized, and released from hematopoietic cells.
- To investigate the impact of post-translational modifications on FasL activity and its potential as an immunotherapy target.
Main Methods:
- Analysis of FasL interactions with adapter proteins involved in cellular trafficking and cytoskeletal organization.
- Investigation of post-translational modifications, including ectodomain shedding, intramembrane proteolysis, phosphorylation, and ubiquitylation.
- Characterization of FasL sorting and release from secretory lysosomes.
Main Results:
- FasL is stored in secretory lysosomes and mobilized to the immunological synapse upon activation, requiring interactions of its cytosolic moiety with adapter proteins.
- Surface FasL expression is regulated by ectodomain shedding and intramembrane proteolysis, yielding soluble and intracellular fragments.
- Post-translational modifications like phosphorylation and ubiquitylation significantly influence various aspects of FasL biology.
Conclusions:
- Fas ligand's function is precisely regulated through complex intracellular trafficking, release mechanisms, and post-translational modifications.
- Understanding these regulatory pathways is critical for developing targeted immunotherapies.
- Further research into FasL biology will inform the development and evaluation of novel therapeutic strategies for cancer and immune-related diseases.
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