The overall objective of the Mouse Management and Pathology Core (Core B) is to raise, maintain, and provide cohorts of specific pathogen-free and genetically standardized p66Shc-/- knockout mice for all research projects in this program project. Also, the core will raise and maintain mice on calorie-restricted, low-carbohydrate and high-carbohydrate/high-fat diets and provide those mice and their tissues to the research projects in order to assess age-related metabolic consequences and clinical and anatomic pathologies. All mice analyzed will be on a congenic C57BL/6J genetic background and maintained in a mouse dedicated vivarium under barrier conditions. Core B will accomplish these objectives using relevant resources and technical expertise drawn primarily from the UC Davis Mouse Biology Program. Core B will fulfill the following two Specific Aims: Specific Aim 1: Provide p66Shc-/- and littermate control mice at selected stages of life (cross-section analysis) in response to caloric restriction diet. p66Shc-/- and wild-type control mice will be bred, and sampled at specific intervals for biochemical and microarray analysis in Projects 1 and 2. The results of this Aim will reveal the extent to which She alters the metabolic response to sustained caloric restriction. Specific Aim 2: Provide p66Shc-/- and littermate control mice for lifespan analysis and assess clinical and anatomic pathologies in response to high-fat/high-carbohydrate and low-carbohydrate diets. Similarly, p66Shc-/- mice resist high-fat diets and are expected to have increased lifespan in that condition, and so an investigation of lifespan-limiting pathology in that condition is important. Aim 2 will serve the hypothesis that a low-carbohydrate thus the underlying diet mimics the effects of caloric restriction and She-deficiency extends lifespan, and pathology will be investigated.