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出典:『Wikipedia』 (2010/06/17 14:37 UTC 版)

英語による解説

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Morpheein – a protein that can form two or more different homo-oligomers (morpheein forms), but must come apart and change shape to convert between forms. The alternate shape may reassemble to a different oligomer. The shape of the subunit dictates which oligomer is formed. The conformational changes necessary to dictate oligomer formation need not be very extensive. Each oligomer has a finite number of subunits (stoichiometry). Morpheeins can interconvert between forms under physiological conditions and can exist as an equilibrium of different oligomers. These oligomers are physiologically relevant and are not misfolded proteins; this distinguishes morpheeins from prions. The different oligomers have distinct functionality. Interconversion of morpheein forms can be a structural basis for allosteric regulation. A mutation that shifts the normal equilibrium of morpheein forms can serve as the basis for a conformational disease. Features of morpheeins can be exploited for drug discovery. The dice image (Fig 1) represents a morpheein equilibrium containing two different monomeric shapes that dictate assembly to a tetramer or a pentamer. The one protein that is established to function as a morpheein is porphobilinogen synthase, though there are suggestions throughout the literature that other proteins may function as morpheeins (for more information please see "Morpheeins Database" in ).