| inactivation | <neurology, physiology> For example of voltage gated sodium channels: process by which sodium channels that have been activated or opened by depolarisation subsequently close during the depolarisation. Distinguished from activation by its slower kinetics. (18 Nov 1997) |
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| radiation inactivation | The technique of inactivating proteins in freeze dried (lyophilised) preparations using high energy particles (e.g. Electrons). One high energy particle can apparently inactivate all of the components of a multisubunit polypeptide, the method is therefore used to determine the molecular weight of functional oligomers. (18 Nov 1997) |
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| X inactivation | <cell biology> The inactivation of one or other of each pair of X chromosomes to form the Barr body in female mammalian somatic cells. Thus tissues whose original zygote carried heterozygous X borne genes should have individual cells expressing one or other but not both of the X borne gene products. The inactivation is thought to occur early in development and leads to mosaicism of expression of such genes in the body. See: Lyon hypothesis. (18 Nov 1997) |
| insertional inactivation | The inactivation of a gene due to the insertion of exogenous genetic material into that gene. (14 Nov 1997) |
| enzyme inactivation | The disappearance of an enzyme's activity during in vitro conditions, such as during a lab preparation of the enzyme, where the enzyme is exposed to conditions not normally found within its environment inside a living cell (like different pH, excess or too little salt, temperature changes, etc.) (09 Oct 1997) |