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A chromatin modifier integrates insulin/IGF-1 signalling and dietary restriction to regulate longevity.

Singh A, Kumar N, Matai L, Jain V, Garg A, Mukhopadhyay A - Aging Cell (2016)

Bottom Line: The downstream transcription factors of the IIS and select DR pathways, DAF-16/FOXO or PHA-4/FOXA, respectively, both transcriptionally regulate the expression of zfp-1.Consequently, zfp-1 is required for the enhanced longevity observed during DR and on knockdown of IIS.Our data reveal how two distinct sensor pathways control an overlapping set of genes, using different downstream transcription factors, integrating potentially diverse and temporally distinct nutritional situations.

View Article: PubMed Central - PubMed

Affiliation: Molecular Aging Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India.

No MeSH data available.


ZFP‐1 influences DAF‐16/FOXO recruitment to its target promoters. (A) ChIP‐PCR to determine DAF‐16 recruitment to different target promoters in WT and zfp‐1(ok554). Binding in WT/zfp‐1(ok554) is normalized to that of daf‐16(‐). Recruitment at a distal region of sod‐3 is taken as control. The graph is plotted from three experiments. Error bars represent standard deviation. **P ≤ 0.01; *P ≤ 0.05 by Student's t‐test. (B) Distribution of ZFP‐1 peaks with respect to DAF‐16/FOXO binding summits as determined by ChIP‐seq experiments (left panel). Distribution of ZFP‐1 reads with respect to DAF‐16 binding summit across all chromosomes (right panel). ZFP‐1 ChIP‐seq data from MODENCODE were reanalysed using our bioinformatic pipeline. (C) Overlap of ZFP‐1 and DAF‐16 direct target genes as determined by ChIP‐seq experiments. (D) Gene Ontology (GO) term analysis of common target genes of DAF‐16/FOXO and ZFP‐1. Only top 15 GO terms that were enriched are shown.
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acel12477-fig-0004: ZFP‐1 influences DAF‐16/FOXO recruitment to its target promoters. (A) ChIP‐PCR to determine DAF‐16 recruitment to different target promoters in WT and zfp‐1(ok554). Binding in WT/zfp‐1(ok554) is normalized to that of daf‐16(‐). Recruitment at a distal region of sod‐3 is taken as control. The graph is plotted from three experiments. Error bars represent standard deviation. **P ≤ 0.01; *P ≤ 0.05 by Student's t‐test. (B) Distribution of ZFP‐1 peaks with respect to DAF‐16/FOXO binding summits as determined by ChIP‐seq experiments (left panel). Distribution of ZFP‐1 reads with respect to DAF‐16 binding summit across all chromosomes (right panel). ZFP‐1 ChIP‐seq data from MODENCODE were reanalysed using our bioinformatic pipeline. (C) Overlap of ZFP‐1 and DAF‐16 direct target genes as determined by ChIP‐seq experiments. (D) Gene Ontology (GO) term analysis of common target genes of DAF‐16/FOXO and ZFP‐1. Only top 15 GO terms that were enriched are shown.

Mentions: We found that knocking down the zfp‐1(2ac) isoform leads to an increased expression of DAF‐16 direct targets like sod‐3 and mtl‐1. In order to understand the nature of this regulation, we asked whether the recruitment of DAF‐16 is influenced by ZFP‐1. For this, we performed ChIP using anti‐DAF‐16 antibody in wild‐type, zfp‐1(ok554) as well as daf‐16(‐), and evaluated DAF‐16 binding at the sod‐3 promoter by quantitative PCR. We found that binding of DAF‐16 increased significantly in the absence of ZFP‐1, on the sod‐3 promoter (Fig. 4A). However, no increase was seen in the distal region of sod‐3. This correlates well with the increase in sod‐3 expression on zfp‐1(2ac) knockdown and showed that ZFP‐1 negatively regulates the direct binding of DAF‐16 to the sod‐3 promoter. Similar observations were made in the case of other DAF‐16 targets (Fig. 4A). Interestingly, ZFP‐1 also negatively regulates the binding of DAF‐16 to its own promoter, forming a feed‐back loop as shown earlier (Cecere et al., 2013). We were unable to generate a daf‐2(e1370);zfp‐1(ok554) or daf‐2(e1368);zfp‐1(ok554) double mutant due to larval lethality, as reported previously (Mansisidor et al., 2011), but anticipate similar mechanism in a daf‐2(‐) scenario. Thus, ZFP‐1 may fine‐tune DAF‐16‐dependent expression of genes by regulating the binding of the transcription factor to its target promoters.


A chromatin modifier integrates insulin/IGF-1 signalling and dietary restriction to regulate longevity.

Singh A, Kumar N, Matai L, Jain V, Garg A, Mukhopadhyay A - Aging Cell (2016)

ZFP‐1 influences DAF‐16/FOXO recruitment to its target promoters. (A) ChIP‐PCR to determine DAF‐16 recruitment to different target promoters in WT and zfp‐1(ok554). Binding in WT/zfp‐1(ok554) is normalized to that of daf‐16(‐). Recruitment at a distal region of sod‐3 is taken as control. The graph is plotted from three experiments. Error bars represent standard deviation. **P ≤ 0.01; *P ≤ 0.05 by Student's t‐test. (B) Distribution of ZFP‐1 peaks with respect to DAF‐16/FOXO binding summits as determined by ChIP‐seq experiments (left panel). Distribution of ZFP‐1 reads with respect to DAF‐16 binding summit across all chromosomes (right panel). ZFP‐1 ChIP‐seq data from MODENCODE were reanalysed using our bioinformatic pipeline. (C) Overlap of ZFP‐1 and DAF‐16 direct target genes as determined by ChIP‐seq experiments. (D) Gene Ontology (GO) term analysis of common target genes of DAF‐16/FOXO and ZFP‐1. Only top 15 GO terms that were enriched are shown.
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acel12477-fig-0004: ZFP‐1 influences DAF‐16/FOXO recruitment to its target promoters. (A) ChIP‐PCR to determine DAF‐16 recruitment to different target promoters in WT and zfp‐1(ok554). Binding in WT/zfp‐1(ok554) is normalized to that of daf‐16(‐). Recruitment at a distal region of sod‐3 is taken as control. The graph is plotted from three experiments. Error bars represent standard deviation. **P ≤ 0.01; *P ≤ 0.05 by Student's t‐test. (B) Distribution of ZFP‐1 peaks with respect to DAF‐16/FOXO binding summits as determined by ChIP‐seq experiments (left panel). Distribution of ZFP‐1 reads with respect to DAF‐16 binding summit across all chromosomes (right panel). ZFP‐1 ChIP‐seq data from MODENCODE were reanalysed using our bioinformatic pipeline. (C) Overlap of ZFP‐1 and DAF‐16 direct target genes as determined by ChIP‐seq experiments. (D) Gene Ontology (GO) term analysis of common target genes of DAF‐16/FOXO and ZFP‐1. Only top 15 GO terms that were enriched are shown.
Mentions: We found that knocking down the zfp‐1(2ac) isoform leads to an increased expression of DAF‐16 direct targets like sod‐3 and mtl‐1. In order to understand the nature of this regulation, we asked whether the recruitment of DAF‐16 is influenced by ZFP‐1. For this, we performed ChIP using anti‐DAF‐16 antibody in wild‐type, zfp‐1(ok554) as well as daf‐16(‐), and evaluated DAF‐16 binding at the sod‐3 promoter by quantitative PCR. We found that binding of DAF‐16 increased significantly in the absence of ZFP‐1, on the sod‐3 promoter (Fig. 4A). However, no increase was seen in the distal region of sod‐3. This correlates well with the increase in sod‐3 expression on zfp‐1(2ac) knockdown and showed that ZFP‐1 negatively regulates the direct binding of DAF‐16 to the sod‐3 promoter. Similar observations were made in the case of other DAF‐16 targets (Fig. 4A). Interestingly, ZFP‐1 also negatively regulates the binding of DAF‐16 to its own promoter, forming a feed‐back loop as shown earlier (Cecere et al., 2013). We were unable to generate a daf‐2(e1370);zfp‐1(ok554) or daf‐2(e1368);zfp‐1(ok554) double mutant due to larval lethality, as reported previously (Mansisidor et al., 2011), but anticipate similar mechanism in a daf‐2(‐) scenario. Thus, ZFP‐1 may fine‐tune DAF‐16‐dependent expression of genes by regulating the binding of the transcription factor to its target promoters.

Bottom Line: The downstream transcription factors of the IIS and select DR pathways, DAF-16/FOXO or PHA-4/FOXA, respectively, both transcriptionally regulate the expression of zfp-1.Consequently, zfp-1 is required for the enhanced longevity observed during DR and on knockdown of IIS.Our data reveal how two distinct sensor pathways control an overlapping set of genes, using different downstream transcription factors, integrating potentially diverse and temporally distinct nutritional situations.

View Article: PubMed Central - PubMed

Affiliation: Molecular Aging Laboratory, National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi, 110067, India.

No MeSH data available.