Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 1 de 1
Filtrar
Mais filtros

Base de dados
Ano de publicação
Tipo de documento
Intervalo de ano de publicação
1.
J Biol Chem ; 290(20): 12753-64, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-25825491

RESUMO

Attenuated nutrient signaling extends the life span in yeast and higher eukaryotes; however, the mechanisms are not completely understood. Here we identify the Ssy1-Ptr3-Ssy5 (SPS) amino acid sensing pathway as a novel longevity factor. A null mutation of SSY5 (ssy5Δ) increases replicative life span (RLS) by ∼50%. Our results demonstrate that several NAD(+) homeostasis factors play key roles in this life span extension. First, expression of the putative malate-pyruvate NADH shuttle increases in ssy5Δ cells, and deleting components of this shuttle, MAE1 and OAC1, largely abolishes RLS extension. Next, we show that Stp1, a transcription factor of the SPS pathway, directly binds to the promoter of MAE1 and OAC1 to regulate their expression. Additionally, deletion of SSY5 increases nicotinamide riboside (NR) levels and phosphate-responsive (PHO) signaling activity, suggesting that ssy5Δ increases NR salvaging. This increase contributes to NAD(+) homeostasis, partially ameliorating the NAD(+) deficiency and rescuing the short life span of the npt1Δ mutant. Moreover, we observed that vacuolar phosphatase, Pho8, is partially required for ssy5Δ-mediated NR increase and RLS extension. Together, our studies present evidence that supports SPS signaling is a novel NAD(+) homeostasis factor and ssy5Δ-mediated life span extension is likely due to concomitantly increased mitochondrial and vacuolar function. Our findings may contribute to understanding the molecular basis of NAD(+) metabolism, cellular life span, and diseases associated with NAD(+) deficiency and aging.


Assuntos
Proteínas de Transporte/metabolismo , Homeostase/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , NAD/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Serina Proteases/metabolismo , Transdução de Sinais/fisiologia , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Proteínas de Transporte/genética , Deleção de Genes , Regulação Fúngica da Expressão Gênica/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Malato Desidrogenase/genética , Malato Desidrogenase/metabolismo , Proteínas de Membrana/genética , NAD/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Serina Proteases/genética , Vacúolos/genética , Vacúolos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA