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Ceramidases
Ceramidase (, ''acylsphingosine deacylase'', ''glycosphingolipid ceramide deacylase'') is an enzyme which cleaves fatty acids from ceramide, producing sphingosine (SPH) which in turn is phosphorylated by a sphingosine kinase to form sphingosine-1-phosphate (S1P). Function Ceramide, SPH, and S1P are bioactive lipids that mediate cell growth, cell proliferation, cellular differentiation, differentiation, apoptosis, cell adhesion, adhesion, and cell migration, migration. Presently, 7 human ceramidases encoded by 7 distinct genes have been cloned: * acid ceramidase (ASAH1) – cell survival * neutral ceramidase (ASAH2, ASAH2B, ASAH2C) – protective against inflammatory cytokines * alkaline ceramidase 1 (ACER1) – mediating cell differentiation by controlling the generation of SPH and S1P * alkaline ceramidase 2 (ACER2) – important for cell proliferation and survival * alkaline ceramidase 3 (ACER3) Clinical significance A deficiency in ASAH1 is associated with Farber disea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASAH2
Neutral ceramidase is an enzyme that in humans is encoded by the ''ASAH2'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... References External links * * Further reading * * * * * * * * * * * * * * {{gene-10-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceramide
Ceramides are a family of waxy lipid molecules. A ceramide is composed of N-acetyl sphingosine and a fatty acid. Ceramides are found in high concentrations within the cell membrane of eukaryotic cells, since they are component lipids that make up sphingomyelin, one of the major lipids in the lipid bilayer. Contrary to previous assumptions that ceramides and other sphingolipids found in cell membrane were purely supporting structural elements, ceramide can participate in a variety of cellular signaling: examples include regulating differentiation, proliferation, and programmed cell death (PCD) of cells. The word ''ceramide'' comes from the Latin ''cera'' ( wax) and ''amide''. Ceramide is a component of vernix caseosa, the waxy or cheese-like white substance found coating the skin of newborn human infants. Pathways for ceramide synthesis There are three major pathways of ceramide generation. First, the sphingomyelinase pathway uses an enzyme to break down sphingomyelin in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASAH1
The ASAH1 gene encodes in humans the ''acid ceramidase'' enzyme. Function This gene encodes a heterodimeric protein consisting of a nonglycosylated alpha subunit and a glycosylated beta subunit that is cleaved to the mature enzyme posttranslationally. The encoded protein catalyzes the synthesis and degradation of ceramide into sphingosine and fatty acid. Mutations in this gene have been associated with a lysosomal storage disorder known as Farber disease and, recently, with a rare neurodegenerative condition known as spinal muscular atrophy with progressive myoclonic epilepsy. Two transcript variants encoding distinct isoforms have been identified for this gene. In melanocytic cells ASAH1 gene expression may be regulated by MITF. As a glioblastoma drug target ASAH1 expression is upregulated following radiation, suggesting it plays a role in conferring radioresistance to glioblastoma and in the development of recurrent glioblastoma. Inhibiting the activity of ASAH1 with c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACER3
Alkaline ceramidase 3 also known as ACER3 is a ceramidase enzyme which in humans is encoded by the ''ACER3'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... References External links * Further reading * * * * Human proteins {{gene-11-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACER2
Alkaline ceramidase 2 also known as ACER2 is a ceramidase enzyme which in humans is encoded by the ACER2 gene. Function The ACER2/sphingosine pathway plays an important role in regulating integrin β1 subunit (ITGB1 Integrin beta-1 (ITGB1), also known as CD29, is a cell surface receptor that in humans is encoded by the ''ITGB1'' gene. This integrin associates with integrin alpha 1 and integrin alpha 2 to form integrin complexes which function as collagen r ...) maturation and cell adhesion mediated by β1 integrins. References External links * Further reading * * * * * Human proteins {{gene-9-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ACER1
Alkaline ceramidase 1 also known as ACER1 is a ceramidase enzyme which in humans is encoded by the ''ACER1'' gene. Function ACER1 mediates cellular differentiation by controlling the generation of sphingosine (SPH) and sphingosine-1-phosphate (S1P). Model organisms Model organisms have been used in the study of ACER1 function. A conditional knockout mouse line called ''Acer1tm1a(EUCOMM)Wtsi'' was generated at the Wellcome Trust Sanger Institute. Male and female animals underwent a standardized phenotypic screen In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological proper ... to determine the effects of deletion. Additional screens performed: - In-depth immunological phenotyping - in-depth bone and cartilage phenotyping References External links * Further reading * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASAH2C
Neutral ceramidase C also known as N-acylsphingosine amidohydrolase 2C or non-lysosomal ceramidase C or ASAH2C is a ceramidase enzyme which in humans is encoded by the ''ASAH2C'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... References Further reading * * * * * * {{gene-10-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ASAH2B
Neutral ceramidase B also known as non-lysosomal ceramidase B or N-acylsphingosine amidohydrolase (non-lysosomal ceramidase) 2B or ASAH2B is a ceramidase enzyme which in humans is encoded by the ASAH2B gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b .... Clinical significance ASAH2B shows reduced expression with increasing age and further reduction in late onset Alzheimer's disease patients. References External links * Further reading * {{gene-10-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Migration
Cell migration is a central process in the development and maintenance of multicellular organisms. Tissue formation during embryonic development, wound healing and immune responses all require the orchestrated movement of cells in particular directions to specific locations. Cells often migrate in response to specific external signals, including chemical signals and mechanical signals. Errors during this process have serious consequences, including intellectual disability, vascular disease, tumor formation and metastasis. An understanding of the mechanism by which cells migrate may lead to the development of novel therapeutic strategies for controlling, for example, invasive tumour cells. Due to the highly viscous environment (low Reynolds number), cells need to continuously produce forces in order to move. Cells achieve active movement by very different mechanisms. Many less complex prokaryotic organisms (and sperm cells) use flagella or cilia to propel themselves. Eukaryot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphingosine
Sphingosine (2-amino-4-trans-octadecene-1,3-diol) is an 18-carbon amino alcohol with an unsaturated hydrocarbon chain, which forms a primary part of sphingolipids, a class of cell membrane lipids that include sphingomyelin, an important phospholipid. Functions Sphingosine can be phosphorylated in vivo via two kinases, sphingosine kinase type 1 and sphingosine kinase type 2. This leads to the formation of sphingosine-1-phosphate, a potent signaling lipid. Sphingolipid metabolites, such as ceramides, sphingosine and sphingosine-1-phosphate, are lipid signaling molecules involved in diverse cellular processes. Biosynthesis Sphingosine is synthesized from palmitoyl CoA and serine in a condensation required to yield dihydrosphingosine. Dehydrosphingosine is then reduced by NADPH to dihydrosphingosine (sphinganine), acylated to dihydroceramide finally oxidized by FAD to ceramide. Sphingosine is then solely formed via degradation of sphingolipid in the lysosom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cell Adhesion
Cell adhesion is the process by which cells interact and attach to neighbouring cells through specialised molecules of the cell surface. This process can occur either through direct contact between cell surfaces such as cell junctions or indirect interaction, where cells attach to surrounding extracellular matrix, a gel-like structure containing molecules released by cells into spaces between them. Cells adhesion occurs from the interactions between cell-adhesion molecules (CAMs), transmembrane proteins located on the cell surface. Cell adhesion links cells in different ways and can be involved in signal transduction for cells to detect and respond to changes in the surroundings. Other cellular processes regulated by cell adhesion include cell migration and tissue development in multicellular organisms. Alterations in cell adhesion can disrupt important cellular processes and lead to a variety of diseases, including cancer and arthritis. Cell adhesion is also essential for in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apoptosis
Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes ( morphology) and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, DNA fragmentation, and mRNA decay. The average adult human loses between 50 and 70 billion cells each day due to apoptosis. For an average human child between eight and fourteen years old, approximately twenty to thirty billion cells die per day. In contrast to necrosis, which is a form of traumatic cell death that results from acute cellular injury, apoptosis is a highly regulated and controlled process that confers advantages during an organism's life cycle. For example, the separation of fingers and toes in a developing human embryo occurs because cells between the digits undergo apoptosis. Unlike necrosis, apoptosis produces cell fragments called apop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
