LIN-28 balances longevity and germline stem cell number in C. elegans through let-7/AKT/DAF-16 axis
Ontology highlight
ABSTRACT:
ORGANISM(S): Caenorhabditis elegans
PROVIDER: GSE86077 | GEO | 2016/08/26
SECONDARY ACCESSION(S): PRJNA340183
REPOSITORIES: GEO
Similar Datasets
Project description:The RNA-binding protein LIN-28 was first found to control developmental timing in Caenorhabditis elegans. Later, it was found to play important roles in pluripotency, metabolism, and cancer in mammals. Here we report that a low dosage of lin-28 enhanced stress tolerance and longevity, and reduced germline stem/progenitor cell number in C. elegans. The germline LIN-28-regulated microRNA let-7 was required for these effects by targeting akt-1/2 and decreasing their protein levels. AKT-1/2 and the downstream DAF-16 transcription factor were both required for the lifespan and germline stem cell effects of lin-28. The pathway also mediated dietary restriction induced lifespan extension and reduction in germline stem cell number. Thus, the LIN-28/let-7/AKT/DAF-16 axis we delineated here is a program that plays an important role in balancing reproduction and somatic maintenance and their response to the environmental energy level-a central dogma of the 'evolutionary optimization' of resource allocation that modulates aging.
| S-EPMC5242300 | biostudies-literature
Project description:Many tissue-specific stem cells maintain the ability to produce multiple cell types during long periods of non-division, or quiescence. FOXO transcription factors promote quiescence and stem cell maintenance, but the mechanisms by which FOXO proteins promote multipotency during quiescence are still emerging. The single FOXO ortholog in C. elegans, daf-16, promotes entry into a quiescent and stress-resistant larval stage called dauer in response to adverse environmental cues. During dauer, stem and progenitor cells maintain or re-establish multipotency to allow normal development to resume after dauer. We find that during dauer, daf-16/FOXO prevents epidermal stem cells (seam cells) from prematurely adopting differentiated, adult characteristics. In particular, dauer larvae that lack daf-16 misexpress collagens that are normally adult-enriched. Using col-19p::gfp as an adult cell fate marker, we find that all major daf-16 isoforms contribute to opposing col-19p::gfp expression during dauer. By contrast, daf-16(0) larvae that undergo non-dauer development do not misexpress col-19p::gfp. Adult cell fate and the timing of col-19p::gfp expression are regulated by the heterochronic gene network, including lin-41 and lin-29. lin-41 encodes an RNA-binding protein orthologous to LIN41/TRIM71 in mammals, and lin-29 encodes a conserved zinc finger transcription factor. In non-dauer development lin-41 opposes adult cell fate by inhibiting the translation of lin-29, which directly activates col-19 transcription and promotes adult cell fate. We find that during dauer, lin-41 blocks col-19p::gfp expression, but surprisingly, lin-29 is not required in this context. Additionally, daf-16 promotes the expression of lin-41 in dauer larvae. The col-19p::gfp misexpression phenotype observed in dauer larvae with reduced daf-16 requires the downregulation of lin-41, but does not require lin-29. Taken together, this work demonstrates a novel role for daf-16/FOXO as a heterochronic gene that promotes expression of lin-41/TRIM71 to contribute to multipotent cell fate in a quiescent stem cell model.
2021-10-09 | GSE179166 | GEO
Project description:The insulin/IGF-1 signalling (IIS) pathway has diverse roles from metabolism to longevity. In Caenorhabditis elegans, the single forkhead box O (FOXO) homologue, DAF-16, functions as the major target of the IIS pathway. One of two isoforms, DAF-16a, is known to regulate longevity, stress response and dauer diapause. However, it remains unclear how DAF-16 achieves its specificity in regulating these various biological processes. Here we identify a new isoform, DAF-16d/f, as an important isoform regulating longevity. We show that DAF-16 isoforms functionally cooperate to modulate IIS-mediated processes through differential tissue enrichment, preferential modulation by upstream kinases, and regulating distinct and overlapping target genes. Promoter-swapping experiments show both the promoter and the coding region of DAF-16 are important for its function. Importantly, in mammals, four FOXO genes have overlapping and different functions, and in C. elegans, a single FOXO/DAF-16 uses distinct isoforms to fine-tune the IIS-mediated processes in the context of a whole organism.
| S-EPMC3109862 | biostudies-literature
Project description:FoxO transcription factors can promote longevity in invertebrates and mammals. In C.elegans, the FoxO family member DAF-16 is required for lifespan extension in the contexts of daf-2/IGFR mutation and germline ablation. The daf-16 genomic locus encodes three distinct groups of transcripts (a,b, and d/f/h). In animals with reduced insulin signaling or ablated germlines, mutations that reduce daf-16a and d/f/h levels without affecting daf-16b reduce lifespan to the same extent as daf-16 null mutations. We reasoned that identifying a set of targets of the daf-16a and d/f/h isoforms that are differentially regulated in two contexts of reduced insulin signaling and in germline ablated animals would enrich for the daf-16 transcriptional targets that are required for longevity. We identified targets that were differentially regulated in daf-2(e1368) and daf-2(e1370) mutants relative to wild-type, and differentially regulated in the opposite direction from WT in compound mutants with both daf-16(mg54), which eliminates the a and d/f/h isoforms, and daf-16(mu86) which is a predicted null allele. We performed a similar analysis in glp-1(e2141) germline ablated animals (omitting the wild-type comparison). We then identified daf-16 targets associated with longevity (dal genes) which were found in all three sets of comparisons.
2019-03-01 | GSE111338 | GEO
Project description:Transcriptional profiling of C. elegans first larval stage whole animals comparing lin-35(n745) mutants and N2 (wild type) at 26 degrees.
2011-01-25 | GSE26824 | GEO
Project description:Transcriptional profiling of C. elegans first larval stage whole animals comparing lin-15B(n744) mutants and N2 (wild type) at 26 degrees.
2011-01-25 | GSE26823 | GEO
Project description:Comparison of miRNA profiles of wildtype and lin-28(n719); lin-46(ma164) Caenorhabditis elegans nematodes at the L1 stage
2012-02-09 | GSE35634 | GEO
Project description:RNA-seq was applied for identifying the change of transcriptome between L1 stage lin-52 mutants and N2, with and without UV after 6h of irradiation.
2023-02-01 | GSE152235 | GEO
Project description:Reduced insulin/IGF-1-like signaling (IIS) extends C. elegans lifespan by upregulating stress response (class I) and downregulating other (class II) genes through a mechanism that depends on the conserved transcription factor DAF-16/FOXO. By integrating genome-wide mRNA expression responsiveness to DAF-16 with genome-wide in vivo binding data for a compendium of transcription factors, we discovered that PQM-1 is the elusive transcriptional activator that directly controls development (class II) genes by binding to the DAF-16-associated element (DAE). DAF-16 directly regulates class I genes only, through the DAF-16-binding element (DBE). Loss of PQM-1 suppresses daf-2 longevity and further slows development. Surprisingly, the nuclear localization of PQM-1 and DAF-16 is controlled by IIS in opposite ways and was also found to be mutually antagonistic. We observe progressive loss of nuclear PQM-1 with age, explaining declining expression of PQM-1 targets. Together, our data suggest an elegant mechanism for balancing stress response and development.
| S-EPMC3763726 | biostudies-literature
Project description:The FOXO transcription factor family is a conserved regulator of longevity and the downstream target of insulin/insulin-like signaling. In Caenorhabditis elegans, the FOXO ortholog DAF-16A and D/F isoforms extend lifespan in daf-2 insulin-like receptor mutants. Here we identify the DAF-21/Hsp90 chaperone as a longevity regulator. We find that reducing DAF-21 capacity by daf-21(RNAi) initiated either at the beginning or at the end of larval development shortens wild-type lifespan. daf-21 knockdown employed from the beginning of larval development also decreases longevity of daf-2 mutant and daf-2 silenced nematodes. daf-16 loss-of-function mitigates the lifespan shortening effect of daf-21 silencing. We demonstrate that DAF-21 specifically promotes daf-2 and heat-shock induced nuclear translocation of DAF-16A as well as the induction of DAF-16A-specific mRNAs, without affecting DAF-16D/F localization and transcriptional function. DAF-21 is dispensable for the stability and nuclear import of DAF-16A, excluding a chaperone-client interaction and suggesting that DAF-21 regulates DAF-16A activation upstream of its cellular traffic. Finally, we show a selective requirement for DAF-21 to extend lifespan of DAF-16A, but not DAF-16D/F, transgenic daf-2 mutant strains. Our findings indicate a spatiotemporal determination of multiple DAF-21 roles in fertility, development and longevity and reveal an isoform-specific regulation of DAF-16 activity.
| S-EPMC6089956 | biostudies-literature