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3',5'-cyclic-nucleotide Phosphodiesterase
3′,5′-cyclic-nucleotide phosphodiesterases (EC 3.1.4.17) are a protein family, family of phosphodiesterases. Generally, these enzymes hydrolyze a nucleoside 3′,5′-cyclic phosphate to a nucleoside 5′-phosphate: :nucleoside 3′,5′-cyclic phosphate + H2O = nucleoside 5′-phosphate They thus control the cellular levels of the cyclic second messengers and the rates of their degradation. Some examples of nucleoside 3′,5′-cyclic phosphate include: *Cyclic adenosine monophosphate, 3′,5′-cyclic AMP *3′,5′-cyclic dAMP *3′,5′-cyclic IMP *Cyclic guanosine monophosphate, 3′,5′-cyclic GMP *3′,5′-cyclic CMP There are 11 distinct phosphodiesterase families (PDE1–PDE11) with a variety in isoforms and splicing having unique three-dimensional structure, kinetic properties, modes of regulation, intracellular localization, cellular expression, and inhibitor sensitivities. Nomenclature The systematic name for this enzyme is 3′,5′-cyclic-nucleotide 5'- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein Family
A protein family is a group of evolutionarily related proteins. In many cases, a protein family has a corresponding gene family, in which each gene encodes a corresponding protein with a 1:1 relationship. The term "protein family" should not be confused with family as it is used in taxonomy. Proteins in a family descend from a common ancestor and typically have similar three-dimensional structures, functions, and significant sequence similarity. Sequence similarity (usually amino-acid sequence) is one of the most common indicators of homology, or common evolutionary ancestry. Some frameworks for evaluating the significance of similarity between sequences use sequence alignment methods. Proteins that do not share a common ancestor are unlikely to show statistically significant sequence similarity, making sequence alignment a powerful tool for identifying the members of protein families. Families are sometimes grouped together into larger clades called superfamilies based on st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
