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Cytoplasm-to-vacuole Targeting
Cytoplasm-to-vacuole targeting (Cvt) is an autophagy-related pathway in yeast. Under vegetative conditions it delivers hydrolases, such as aminopeptidase Aminopeptidases are enzymes that catalyze the cleavage of amino acids from the amino terminus (N-terminus) of proteins or peptides (exopeptidases). They are widely distributed throughout the animal and plant kingdoms and are found in many subcell ... 1 (Ape1), to the vacuole. This makes the cvt pathway the only known biosynthetic pathway to utilize the machinery of autophagy for operation. Nomenclature The abbreviation Cvt comes from the emphasis Cytoplasm vacuole targeting, not from Cytoplasm-to-vacuole targeting. References Cellular processes {{hydrolase-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Autophagy
Autophagy (or autophagocytosis; from the Ancient Greek , , meaning "self-devouring" and , , meaning "hollow") is the natural, conserved degradation of the cell that removes unnecessary or dysfunctional components through a lysosome-dependent regulated mechanism. It allows the orderly degradation and recycling of cellular components. Although initially characterized as a primordial degradation pathway induced to protect against starvation, it has become increasingly clear that autophagy also plays a major role in the homeostasis of non-starved cells. Defects in autophagy have been linked to various human diseases, including neurodegeneration and cancer, and interest in modulating autophagy as a potential treatment for these diseases has grown rapidly. Four forms of autophagy have been identified: macroautophagy, microautophagy, chaperone-mediated autophagy (CMA), and crinophagy. In macroautophagy (the most thoroughly researched form of autophagy), cytoplasmic components (like mit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminopeptidase
Aminopeptidases are enzymes that catalyze the cleavage of amino acids from the amino terminus (N-terminus) of proteins or peptides (exopeptidases). They are widely distributed throughout the animal and plant kingdoms and are found in many subcellular organelles, in cytosol, and as membrane components. Aminopeptidases are used in essential cellular functions. Many, but not all, of these peptidases are zinc metalloenzymes. Some aminopeptidases are monomeric, and others are assemblies of relatively high mass (50 kDa) subunits. cDNA sequences are available for several aminopeptidases and a crystal structure of the open state of human endoplasmic reticulum Aminopeptidase 1 ERAP1 is presented here. Amino acid sequences determined directly or deduced from cDNAs indicate some amino acid sequence homologies in organisms as diverse as ''Escherichia coli'' and mammals, particularly in catalytically important residues or in residues involved in metal ion binding. One important aminopeptidas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosynthesis
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism. The prerequisite elements for biosynthesis include: precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes which may require coenzymes (e.g.NADH, NADPH). These elements create monomers, the building blocks for macromolecules. Some important biological macromolecules include: proteins, which are composed of amino acid monomers joined via peptide bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
