Related Experiment Video

Updated: Aug 8, 2026

Isolation of Labile Multi-protein Complexes by in vivo Controlled Cellular Cross-Linking and Immuno-magnetic Affinity Chromatography
10:50

Isolation of Labile Multi-protein Complexes by in vivo Controlled Cellular Cross-Linking and Immuno-magnetic Affinity Chromatography

Published on: March 10, 2010

Identification and characterization of a dimerization domain in CED-6, an adapter protein involved in engulfment of

H P Su1, E Brugnera, W Van Criekinge

  • 1Beirne Carter Center for Immunology Research and the Department of Microbiology, University of Virginia, Charlottesville, Virginia 22908, USA.

The Journal of Biological Chemistry
|March 29, 2000
PubMed

Insights

CED-6, an adapter protein, forms dimers through a leucine zipper domain. This dimerization is crucial for its function in clearing apoptotic cells and is conserved across species.

Area of Science:

  • Cell biology
  • Molecular biology
  • Developmental biology

Background:

  • Phagocytosis of apoptotic cells is essential for multicellular organism development and tissue homeostasis.
  • The molecular mechanisms underlying apoptotic cell clearance are actively being investigated.
  • CED-6, an adapter protein, has been identified in Caenorhabditis elegans and humans, playing a role in engulfment.

Purpose of the Study:

  • To investigate the structural and functional properties of the CED-6 protein.
  • To determine if CED-6 undergoes dimerization and to identify the domain responsible for this interaction.
  • To explore the implications of CED-6 dimerization in the process of apoptotic cell engulfment.

Main Methods:

  • Co-immunoprecipitation studies to assess protein interactions.
  • Yeast two-hybrid assays to confirm CED-6 self-interaction.
  • Gel filtration chromatography to determine CED-6 molecular weight and oligomeric state.
  • Mutational analysis of the leucine zipper domain.

Main Results:

  • CED-6 protein forms dimers in vivo, as evidenced by multiple experimental approaches.
  • A leucine zipper domain adjacent to the phosphotyrosine-binding (PTB) domain mediates CED-6 dimerization.
  • The leucine zipper domain is both necessary and sufficient for CED-6 dimerization.
  • CED-6 dimerization is evolutionarily conserved, observed in C. elegans, rodent, and human proteins.

Conclusions:

  • CED-6 functions as a dimer, mediated by its leucine zipper domain.
  • Dimerization of CED-6 may be critical for its ability to bind ligands and execute its role in apoptotic cell phagocytosis.
  • Understanding CED-6 dimerization provides insights into the molecular regulation of programmed cell death completion.

More Related Videos

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages06:47

Experimental Analysis of Apoptotic Thymocyte Engulfment by Macrophages

Published on: May 24, 2019

Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex07:17

Measuring Composition of CD95 Death-Inducing Signaling Complex and Processing of Procaspase-8 in this Complex

Published on: August 2, 2021

Related Concept Videos

Pinching-off of Coated Vesicles01:32

Pinching-off of Coated Vesicles

Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...
Export of Misfolded Proteins out of the ER01:32

Export of Misfolded Proteins out of the ER

After folding, the ER assesses the quality of secretory and membrane proteins. The correctly folded proteins are cleared by the calnexin cycle for transport to their final destination, while misfolded proteins are held back in the ER lumen. The ER chaperones attempt to unfold and refold the misfolded proteins but sometimes fail to achieve the correct native conformation. Such terminally misfolded proteins are then exported to the cytosol by ER-associated degradation or ERAD pathway for...
The Extrinsic Apoptotic Pathway01:17

The Extrinsic Apoptotic Pathway

The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
Phagocytosis of Apoptotic Cells01:17

Phagocytosis of Apoptotic Cells

Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or  immature dendritic cells. Non-professional phagocytes such as  epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes. 
Normal cells contain receptors that prevent them from being recognized by phagocytes.
Clathrin Coated Vesicles01:12

Clathrin Coated Vesicles

Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...
Assembly of Signaling Complexes01:30

Assembly of Signaling Complexes

Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...