Description
Key facts
Detection method:Fluorescent,
Sample types:Cell culture extracts, Tissue Extracts,
Assay type:Semi-quantitative,
Sensitivity:= 1 U/mL,
Assay Platform:Microplate reader
Product details:
Acid Sphingomyelinase Assay Kit (Fluorometric) (ab190554) provides one of the most sensitive methods for detecting acidic sphingomyelinase (SMase) activity in cell extracts, or for screening the effect of inhibitors on acid SMase activity. The kit uses the AbRed Indicator as a fluorogenic probe to indirectly quantify the phosphocholine produced from the hydrolysis of sphingomyelin (SM) by sphingomyelinase (SMase). The fluorescence intensity of AbRed is proportional to the formation of phosphocholine, therefore proportional to the SMase activity.
This product can be used for measuring the SMase activity in cell extracts or solutions such as blood. The kit is an optimized "mix and read" assay which is compatible with HTS liquid handling instruments.
This assay is semi-quantitative as it does not contain a SMase standard for calibration. When a known concentration of sphingomyelinase is used, the assay can detect as low as 1 U/mL acidic sphingomyelinase in solution.
Other notes
This product was previously called Acidic Sphingomyelinase Assay Kit (Fluorimetric).
Sphingomyelinase (SMase; sphingomyelin phosphodiesterase, EC 3.1.4.12) is responsible for cleaving sphingomyelin (SM) to phosphocholine and ceramide. Activation of SMase plays an important role in cellular responses such as regulation of cell growth, cell differentiation, cell cycle arrest and programmed cell death. Five types of sphingomyelinase have been identified, based on their cation dependence and optimal pH of action: lysosomal acid SMase, secreted zinc-dependent acid SMase, magnesium-dependent neutral SMase, magnesium-independent neutral SMase and alkaline SMase. Among those five types, lysosomal acidic SMase and magnesium-dependent neutral SMase are considered to be the major factors for the production of ceramide in cellular stress responses.
Properties and Storage Information:
Shipped at conditions-Blue Ice, Appropriate short-term storage conditions--20°C, Appropriate long-term storage conditions--20°C, Storage information--20°C
Supplementary Information:
This supplementary information is collated from multiple sources and compiled automatically.
Acid sphingomyelinase (ASMase) also known as sphingomyelin phosphodiesterase 1 or NP is an enzyme involved in sphingolipid metabolism. ASMase has a mass of approximately 75 kDa and appears in lysosomes where it converts sphingomyelin to ceramide and phosphorylcholine. This enzyme is important in maintaining cellular lipid balance and signaling. Expression of ASMase occurs in various tissues such as the liver spleen and brain.
Biological function summary
ASMase plays a role in membrane microdomain composition through its involvement in ceramide production. It participates in generating ceramide-enriched platforms that facilitate the clustering of signaling molecules. Ceramide acts as a second messenger in multiple cellular processes including apoptosis proliferation and inflammation. ASMase operates in the lysosomal lipid degradation pathway and connects with other lysosomal enzymes to modulate lipid turnovers such as glucosylceramidase affecting downstream cellular functions.
Pathways
Sphingolipid metabolism involves ASMase. This enzyme participates in the ceramide signaling pathway influencing apoptosis and stress responses. Related proteins in this pathway include casein kinase II which phosphorylates ASMase and cathepsin D involved in the lysosomal degradation process. ASMase activity alters ceramide levels impacting pro-apoptotic and pro-survival signals mediated by related proteins in the cell signaling network.
ASMase deficiency connects to Niemann-Pick disease types A and B characterized by lipid accumulation in lysosomes. Mutations in the ASMase gene lead to impaired enzyme function resulting in excessive sphingomyelin storage and cell damage. The disorder links ASMase to proteins such as hexa-beta-N-acetylglucosaminidase which is affected in other lysosomal storage disorders. Research shows that ASMase activity also influences cardiovascular diseases by regulating ceramide and cholesterol levels in atherosclerotic lesions connecting it to inflammatory pathways involving adhesion molecules and cytokines.
