Chemical genetic screen in fission yeast reveals roles for vacuolar acidification, mitochondrial fission, and cellular GMP levels in lifespan extension
AGING CELL
Authors: Stephan, Jessica; Franke, Jacqueline; Ehrenhofer-Murray, Ann E.
Abstract
The discovery that genetic mutations in several cellular pathways can increase lifespan has lent support to the notion that pharmacological inhibition of aging pathways can be used to extend lifespan and to slow the onset of age-related diseases. However, so far, only few compounds with such activities have been described. Here, we have conducted a chemical genetic screen for compounds that cause the extension of chronological lifespan of Schizosaccharomyces pombe. We have characterized eight natural products with such activities, which has allowed us to uncover so far unknown anti-aging pathways in S.pombe. The ionophores monensin and nigericin extended lifespan by affecting vacuolar acidification, and this effect depended on the presence of the vacuolar ATPase (V-ATPase) subunits Vma1 and Vma3. Furthermore, prostaglandin J(2) displayed anti-aging properties due to the inhibition of mitochondrial fission, and its effect on longevity required the mitochondrial fission protein Dnm1 as well as the G-protein-coupled glucose receptor Git3. Also, two compounds that inhibit guanosine monophosphate (GMP) synthesis, mycophenolic acid (MPA) and acivicin, caused lifespan extension, indicating that an imbalance in guanine nucleotide levels impinges upon longevity. We furthermore have identified diindolylmethane (DIM), tschimganine, and the compound mixture mangosteen as inhibiting aging. Taken together, these results reveal unanticipated anti-aging activities for several phytochemicals and open up opportunities for the development of novel anti-aging therapies.
The Prevalence of Nine Genetic Disorders in a Dog Population from Belgium, the Netherlands and Germany
PLOS ONE
Authors: Broeckx, Bart J. G.; Coopman, Frank; Verhoeven, Geert E. C.; Van Haeringen, Wim; van de Goor, Leanne; Bosmans, Tim; Gielen, Ingrid; Saunders, Jimmy H.; Soetaert, Sandra S. A.; Van Bree, Henri; Van Neste, Christophe; Van Nieuwerburgh, Filip; Van Ryssen, Bernadette; Verelst, Elien; Van Steendam, Katleen; Deforce, Dieter
Abstract
The objective of this study was to screen a dog population from Belgium, the Netherlands and Germany for the presence of mutant alleles associated with hip dysplasia (HD), degenerative myelopathy (DM), exercise-induced collapse (EIC), neuronal ceroid lipofuscinosis 4A (NCL), centronuclear myopathy (HMLR), mucopolysaccharidosis VII (MPS VII), myotonia congenita (MG), gangliosidosis (GM1) and muscular dystrophy (Duchenne type) (GRMD). Blood samples (K3EDTA) were collected for genotyping with Kompetitive Allele Specific PCR (n = 476). Allele and genotype frequencies were calculated in those breeds with at least 12 samples (n = 8). Hardy-Weinberg equilibrium was tested. Genetic variation was identified for 4 out of 9 disorders: mutant alleles were found in 49, 15, 3 and 2 breeds for HD, DM, EIC and NCL respectively. Additionally, mutant alleles were identified in crossbreeds for both HD and EIC. For HD, DM, EIC and NCL mutant alleles were newly discovered in 43, 13, 2 and 1 breed(s), respectively. In 9, 2 and 1 breed(s) for DM, EIC and NCL respectively, the mutant allele was detected, but the respective disorder has not been reported in those breeds. For 5 disorders (HMLR, MPS VII, MG, GM1, GRMD), the mutant allele could not be identified in our population. For the other 4 disorders (HD, DM, EIC, NCL), prevalence of associated mutant alleles seems strongly breed dependent. Surprisingly, mutant alleles were found in many breeds where the disorder has not been reported to date.