Related Experiment Video
Updated: Jun 27, 2026
10:52
Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
Published on: January 6, 2016
Sphingolipids in mammalian cell signalling
1Department of Medicine, University of Manchester, Manchester Royal Infirmary, United Kingdom. johanian@man.ac.uk
Cellular and Molecular Life Sciences : CMLS
|January 30, 2002
Summary
Sphingolipids, like ceramide, regulate cell functions and are key in cell signaling. Sphingosine-1-phosphate metabolites are crucial for cell proliferation, differentiation, and apoptosis, impacting cardiovascular development.
Area of Science:
- Cellular Biology
- Biochemistry
- Molecular Signaling
Background:
- Sphingolipids and metabolites (ceramide, sphingosine, sphingosine-1-phosphate) are vital for cellular processes like differentiation, senescence, apoptosis, and proliferation.
- Ceramide, a key second messenger, is synthesized via hydrolysis or de novo pathways, with levels elevated by various stimuli.
- Sphingolipids are integral to specialized membrane microdomains (lipid rafts), influencing receptor aggregation and immune responses.
Purpose of the Study:
- To elucidate the multifaceted roles of sphingolipids and their metabolites in cellular signaling pathways.
- To highlight the significance of ceramide compartmentalization and its impact on cellular responses.
- To underscore the importance of sphingosine-1-phosphate signaling in cellular functions and embryonic development.
Main Methods:
- Analysis of sphingolipid metabolism and signaling pathways.
- Investigation of ceramide production and localization.
- Examination of sphingosine-1-phosphate's extracellular and intracellular signaling mechanisms.
Main Results:
- Sphingolipids regulate critical cellular processes including differentiation, senescence, apoptosis, and proliferation.
- Cellular compartmentalization of ceramide production influences its interaction with target proteins.
- Sphingosine-1-phosphate acts through G protein-coupled receptors and intracellular targets, affecting proliferation, differentiation, and apoptosis.
Conclusions:
- Sphingolipid signaling is fundamental to cellular homeostasis and responses.
- The localization of sphingolipid metabolism is critical for precise cellular control.
- Sphingosine-1-phosphate signaling is essential for embryonic cardiovascular development, particularly through EDG receptors.
Related Concept Videos
01:32Membrane Lipids
Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as 20% in the inner mitochondrial membrane or as high as 80% in the myelin sheath present around the nerve cells.
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
01:42Phosphoinositides and PIPs
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
01:32Types of Signaling Molecules
In multicellular organisms, many molecules transmit signals between cells to pass information. These signals vary in complexity and include small peptides, nucleotides, steroids, fatty acid derivatives, and dissolved gases such as nitric oxide. Some signaling molecules diffuse through the plasma membrane to act locally between neighboring cells or travel long distances. Others remain attached to the cell surface, transmitting information to other cells only when they make contact. In some...
01:15Amplifying Signals via Second Messengers
Many receptor binding ligands are hydrophilic; they do not cross the cell membrane but bind to cell-surface receptors. Thus, their message must be relayed by second messengers present in the cell cytoplasm. There are several second messenger pathways, each with its own way of relaying information. For example, the G protein-coupled receptors can activate both phosphoinositol and cyclic AMP (cAMP) second messenger pathways. The phosphoinositol pathway is active when the receptor induces...
01:11IP3/DAG Signaling Pathway
Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and produces two-second...
01:32Types of Signaling Molecules
In multicellular organisms, many molecules transmit signals between cells to pass information. These signals vary in complexity and include small peptides, nucleotides, steroids, fatty acid derivatives, and dissolved gases such as nitric oxide. Some signaling molecules diffuse through the plasma membrane to act locally between neighboring cells or travel long distances. Others remain attached to the cell surface, transmitting information to other cells only when they make contact. In some...