Deacetylases of the Sir2 family regulate lifespan and response to stress. We have examined the evolutionary history of Sir2 and Hst1. which arose by gene duplication in budding yeast and which participate in distinct mechanisms of gene repression. In Saccharomyces cerevisiae. https://www.countryscenesaddleryandpetsuppliers.shop/product-category/western-show-halters/