Deficient Mouse Mutants Research Articles

Catecholamine biosynthesis and the activity of a number of copper-dependent enzymes in the copper deficient mottled mouse mutants

1. The activity of the copper enzymes cytochrome c oxidase and superoxide dismutase is reduced in brain tissue from the copper deficient brindled ( Mo br ) mutant in the mouse. In contrast, the activity of copper-enzymes in liver tissue is unaffected. 2. An elevated activity of adrenal dopamine-β-hydroxylase in blotchy ( Mo blo ) hemizygotes is also reported, together with a reduction in adrenal tissue from brindled hemizygotes in the activities of phenylethanolamine N-methyltransferase and monoamine oxidase, and in the total concentration of catecholamines. 3. The significance of these results to the regulation of cathecholamine biosynthesis is discussed.

Long chain fatty acid formation: key step in myelination studied in mutant mice.

MYELIN is the most stable membrane known and the fact that it contains ten times as much long chain sphingolipid as any other known membrane structure has led to the suggestion that the long chain fatty acids (> 18 carbon atoms) in these sphingolipids are concerned in the stability of myelin1,2. The finding3,4 of a myelin deficient mouse mutant whose galactolipids and sphingomyelin lack long chain fatty acids led us to investigate whether the elaboration of long chain sphingolipid molecules is a key step in myelin formation. The comparison of histological and biochemical events related to myelination in normal and myelin deficient mutant mice supports the hypothesis that in the events leading to adult myelin, the appearance of fatty acids with 24 carbon atoms follows the appearance of cerebrosides and sulphatides in myelin.