Factors

We need to know every factor which determines lifespan.

Lifespan factors often but not always originate from defined genetic elements. They are not just genes, by definition they can be anything for which a Classifications schema can be build for that is related to the regulation of lifespan, such entities may include Single-Nucleotide Polymorphism, transcript variants, proteins and their complexes, compounds (i.e. small molecules like metabolites and drugs), etc. A factor should be based on a defined molecular entity or genomic position and been classified. It shall be highly flexible and scalable Concept.

While individual lifespan factors within each species or precise defined molecular entities will be captured within the Lifespan App, Data Entries of the Data App may summarize for instance the relevance of each factor class (e.g. homologous group; chemical derivate of related structure and properties, etc.) as well as draw overall conclusions. o

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  • symbol name observation species
    MDH1 Malate DeHydrogenase 1 Overexpression of MDH1 extends replicative lifespan by 25% and does not synergize with 0.5% glucose restriction [18381895]. Budding yeast
    NDE1 NADH Dehydrogenase, External 1 Overexpression of NDE1 and NDE2 increases intracellular NAD/NADH ratio by lowering NADH concentration and increases replicative lifespan by 20-25%. This lifespan extension is non-additive 0.5% glucose restriction [14724176]. Deletion of NDE1 extends chronological lifespan [16436509]. Budding yeast
    NDE2 NADH Dehydrogenase, External 2 Overexpression of NDE1 and NDE2 increases intracellular NAD/NADH ratio by lowering NADH concentration and increases replicative lifespan by 20-25%. This lifespan extension is non-additive with 0.5% glucose restriction [14724176]. Budding yeast
    Sir2 Overexpression of Sir2 (alias dSir2) extends lifespan by up to 57% and specifically median lifespan by 40-60%, whereas a decrease in Sir2 activity by mutation blocks the life-extending effect of caloric reduction or rpd3 mutations [15520384]. rpd3 mutants fed normal food and wild-type fed a low-calorie diet increase dSir2 expression two-fold [12459580]. Sir2 mutation does not reduce lifespan under AL. Ubiquitous Sir2 overexpression causes a 4-fold increase in Sir2 mRNA expression and an up to 57% increase in average lifespan (29% for females and 18% for males). A 10 - 20% increase in Sir2 mRNA levels causes no lifespan extension. High levels of Sir2 protein is found in nuclei of neurons and in nuclei and cytoplasm of fat body cells. Neuronal Sir2 overexpression extends average lifespan by 52% in females and 20% in males. Motor-neuronal specific expression fails to cause lifespan extension. Flies with no or with several decreased Sir2 gene function have no lifespan extension under DR. DR fails to cause further increase in lifespan or even reduces lifespan toward normal of Sir2 overexpression mutants. Mild Sir2 overexpression in the fat-body extends lifespan and reduces relative body fat content in both males and females [22661237]. Sir2 in the adult fat body regulates longevity in a diet-depending manner. A diet-dependent lifespan phenotype of Sir2 perturbations (both knockdown and overexpression) in the fat-body, but not in muscles, negates the effects of background genetic mutants. Sir2 knockdown abrogates fat-body dFoxo-dependent lifespan extension [23246004]. Decreased expression of Sir2 and Sir2-like genes in all cells causes lethality during development. Suppression of the Sir2 in neurons decreases the median lifespan by 10-30%, while ubiquitinous silinecing of the Sir2-like genes shortens lifespan. The effects are server at 28°C that at 25°C [17159295]. Fruit fly
    VMA1 Vacuolar Membrane Atpase 1 Overexpression of VMA1 increases vacuolar acidity and suppresses age-induced mitochondrial dysfunction of aged cells (17 or 18 cell divisions) which requires the V-ATPase activity. VMA1 overexpression significantly increases mean, median and maximum lifespan by 39 - 45%, 39 - 48% and 50 - 60%, respectively. DR (0.5% glucose restriction) does not further increase the lifespan of VMA1 overexpression strain [23172144]. Budding yeast
    ucp2 uncoupling protein 2 Overexpression of zebrafish's ucp2 in nematode increases mean, median, and maximum lifespan by 42, 40, and 26%, which is non-additive with sDR [22737090].
    pha-4 defective PHArynx development 4 pha-4 is required for multiple forms of DR. RNAi of pha-4 completely cancels out the lifespan extension of eat-2 mutation. Mutants of pha-4 do not respond to bacterial DR. Therefore, loss of pha-4 completely blocks the response to varying food concentration. Moreover, pha-4 expression is increased in response to DR in wild-type. pha-4 overexpression increases longevity of wild-type only slightly, but significant that of daf-16 mutants. The response to DR involves the PHA-4-dependent expression of sod-1, sod-2 and sod-5. Reduction of pha-4 does not suppress the long lifespan of daf-2 mutants or animals with defective electron transport chain [17476212]. IF significantly extends lifespan of pha-4 [19079239]. sDR extends lifespan of mutants with a temperature sensitive allele of pha-4 or pha-4 RNAi knockdown, but not daf-16 RNAi [19239417]. PHA-4 may play a role in the life-extending effects of dietary restriction. RNAi of pha-4 decreases lifespan of wild-type worms, but not of daf-2 mutants or of animals with defective electron transport chains. Nematode
    hsf-1 Heat Shock Factor 1 RNA interference of hsf-1 suppresses normal dauer formation and life-extension due to insulin-like signaling [14668486]. hsf-1 overexpression extends mean, median, and maximum lifespan by 37, 35, and 29%[22737090]. hsf-1 RNAi abrogates lifespan extension by daf-2(e1370) mutation, but not eat-2(ad1116) or isp-1(qm150). HSF-1, like DAF-16, is required for daf-2 mutations to extend lifespan [12750521]. A mutant allele of hsf-1 slightly decreases lifespan under AL, but cancels out the lifespan extension effect of bDR. hsf-1 RNAi also prevents lifespan extension by bDR. bDR significantly reduces paralysis of Q35YFP or ABeta42 transgenic animals and hsf-1 RNAi totally cancels this effect. DR confers a general protective effect against proteotoxicity and promotes longevity by a mechanism involving hsf-1 [18331616]. Glucose or glycerol does not shorten the lifespan of hsf-1 mutants. Glucose treatment completely suppresses the long lifespan caused by hsf-1 overexpression [19883616]. sDR extends the lifespan of hsf-1 mutant with a premature stop codon, that eliminates activation domain, and that of wild-type to a similar extent [19239417]. hsf-1 RNAi attenuates lifespan extension by bDR, but only partially that of daf-2 mutation. hsf-1 RNAi attenuates protection against oxidative stress by bDR. hsf-1 expression is induced by bDR [19924292]. RNAi of hsf-1 shortens median and maximum lifespan by approximately 35%. hsf-1 RNAi animals exhibit phenotypes associated with accelerated aging (as assyed by Nomarsky microscopy) [12136014]. Nematode
    skn-1 SKiNhead 1 RNA interference of or mutations in skn-1 prevent the life-extension effects of dietary restriction [17538612]. skn-1 transgenes that overexpress a constitutive nuclear form of SKN-1 in the intestine extend the mean lifespan by 5-21%, independently of DAF-16 [18358814]. skn-1 mutation does not alter lifespan under AL, but cancels out the lifespan extension effect of lDR or food variation at all. Response to lDR in skn-1 mutant is restored by ectopic expression of skn-1 in ASI neurons and gut. Ectopic expression of skn-1b in ASI neurons rescued lDR longevity defects of skn-1. Ablation of ASI neurons completely suppresses the response to DR in wild-type or daf-16 mutants and cause a small increase in basal longevity of wild-type but not daf-16 mutants. lDR significantly increases SKN-1 expression in ASI neurons. lDR worms exhibit elevated respiration, which is absent in skn-1 mutants. skn-1 is necessary for increased respiration and the increase in respiration is necessary for lDR longevity effect, because two different inhibitors of mitochondrial electron transport chain complex III, myxothiazol and antimycin, suppress lDR longevity without shortening lifespan under AL. In contrast, the long life of a daf-2 mutant is not affected by antimycin. Some isoforms of SKN-1 are expressed from an operon downstream of bec-1. Beclin-1 mediates autophagy induced by nutrient deprivation. Therefore, skn-1 might be regulated by nutritional stress [17538612]. IF significantly extends lifespan of skn-1 mutants [19079239]. sDR extends lifespan of a skn-1 loss-of-function mutant (which displays a premature stop codon in all three isoforms) and wild-type to a similar extent [19239417]. skn-1(zu67) mutation decreases mean, median, and maximum lifespan by 11-23, 13-28 and 12-23%, respectively, and totally cancels out lifespan extension by ragc-1 RNAi [22560223]. Nematode
    wwp-1 WW domain Protein (E3 ubiquitin ligase) 1 RNA interference of wwp-1 decreases median lifespan by 9% in wild-type animals and 24% in daf-2 mutants [18006689]. Loss of wwp-1 function by RNAi or mutation reduces lifespan at 25 degree Celsius, but not 20 degree Celsius. wwp-1 overexpression extends lifespan by up to 20%. Reduced levels of wwp-1 completely suppress the extended longevity of eat-2 mutants. Lifespan of wwp-1 mutants across entire food concentration range by bacterial dilution in liquid culture or on solid plates does not noticeable change. There is no difference in wwp-1 mRNA levels under AL and DR. RNAi reduction of pha-4, but not of daf-16 suppresses increased longevity by wwp-1 overexpression. Mutations in iron sulphur component of complex III, isp-1, increases longevity by reducing mitochondrial function. wwp-1 RNAi does not suppress the extended lifespan of isp-1 mutants and has only minor suppressive effects on lifespan of another mitochondrial mutant, clk-1, and in cyc-1 RNAi treated worms. RNAi depletion of wwp-1 has no effect on long lifespan of daf-2 mutants [19553937]. Nematode
    sir-2.1 Yeast SIR related 1 sir-2.1 deletion slightly reduces lifespan of wild-type [16860373]. sir-2.1 overexpression extends lifespan by about 50% and this lifespan extension depends on DAF-16 activity as it is suppressed by mutation in daf-16 and it does not synergize with daf-2 [11242085]. sir-2.1 suppresses longevity of unc-13 and eat-2, but not daf-2 or unc-64 mutants. sir-2.1 is therefore partially required for lifespan extension from mutation of eat-2 [16860373], but is completely independent for lifespan extension from DR using a reduced feeding protocol [Kaeberlein et al. in press]. sDR increases lifespan of wild-type and sir-2.1 mutants to the same extent [19239417]. Overrexpression of sir-2.1 synergizes with TGF-beta mutation (daf-4 and daf-1) for dauer formation [11242085]. Nematode
    trx-1 ThioRedoXin 1 Thioredoxins regulate many cellular redox processes. trx-1 is mainly associated with neurons and is expressed in ASJ ciliated sensory neurons and to some extent also on the posterior-most internal cells. trx-1 reduces protein disulfides in the presence of a heterologous thioredoxin reductase. trx-1 null mutant display reduced mean and maximum lifespan [16387300]. Mutants with a deletion in the trx-1 gene display a decrease in lifespan and are sensitive to oxidative stress [16324156]. trx-1 overexpression extends lifespan in wild-type but not in eat-2 mutants. trx-1 deletion completely suppresses the lifespan extension caused by eat-2 mutation, but only partially suppresses that by daf-2 or osm-5 mutations. Ectopic expression of trx-1 in ASJ neurons (but not in the intestine) in trx-1 mutants rescues the lifespan-extension conferred by eat-2 mutation. trx-1 overexpression extends lifespan of wild-type but not in eat-2 mutants. trx-1 deletion almost completely suppresses lifespan extension induced by dietary deprivation (DD). DD upregulates trx-1 expression in ASJ neurons. DR activates trx-1 in ASJ neurons which in turn triggers a trx-1-dependent non-cell autonomous mechanism to extend adult lifespan [21334311]. Nematode
    Cbs Ubiquitous or neuron-specific transgenic overexpression of Cbs enhances longevity in fully-fed animals. Cbs RNAi partially abrogates increased lifespan by DR, but has no effect on fully fed animals. Cbs upregulation is required for increased lifespan under low-nutrient conditions. Response of male flies to DR is muted in comparison with females. Adult-specific ubiquitous expression of Cbs is sufficient to increase female mean and maximum lifespan by 12 - 43% and 10%, respectively. Males, whose lifespan is relatively less affected by DR, exhibite a smaller, but still significant increase in lifespan by 7% upon Cbs overexpression. Neuronal overexpression also increases lifespan, albeit modestly (approximately 12% mean and 15% maximum lifespan extension), whereas overexpression in the fat body and in the gut has no effect [21930912]. Fruit fly
    Factors are an extension of GenAge and GenDR.

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