Deep sequencing of small RNAs from whole nematode C. elegans during aging
Ontology highlight
ABSTRACT: MicroRNAs (miRNAs) have been implicated in gene regulation in many complex processes, including aging. Moreover, expression levels of many miRNAs are altered during aging, though we know little about the mechanisms that regulate this process. To address these issues, we investigated the network of regulatory factors that interact with miRNAs during aging. We found miR-71, a known promoter of normal lifespan, to be an especially important regulator of alg-1/Argonaute. Here we show that increased ALG-1 expression in aging mir-71 loss-of-function mutants was associated with an increased global miRNA abundance and deregulation of mRNA expression. Further, variability in gene expression and lifespan are diminished in mir-71 mutants. Thus, miR-71 appears to promote normal lifespan by directly repressing the expression of alg-1 and indirectly regulating miRNA expression levels and noise. Our findings demonstrate the broad impacts of miRNAs on gene regulation during aging.
Project description:MicroRNAs (miRNAs) have been implicated in gene regulation in many complex processes, including aging. Moreover, expression levels of many miRNAs are altered during aging, though we know little about the mechanisms that regulate this process. To address these issues, we investigated the network of regulatory factors that interact with miRNAs during aging. We found miR-71, a known promoter of normal lifespan, to be an especially important regulator of alg-1/Argonaute. Here we show that increased ALG-1 expression in aging mir-71 loss-of-function mutants was associated with an increased global miRNA abundance and deregulation of mRNA expression. Further, variability in gene expression and lifespan are diminished in mir-71 mutants. Thus, miR-71 appears to promote normal lifespan by directly repressing the expression of alg-1 and indirectly regulating miRNA expression levels and noise. Our findings demonstrate the broad impacts of miRNAs on gene regulation during aging.
Project description:Cellular response to redox imbalance is crucial for organismal health. microRNAs are implicated in stress responses. ALG-1, the C. elegans ortholog of human AGO2, plays an essential role in microRNA processing and function. Here we investigated the mechanisms governing ALG-1 expression in C. elegans and the players controlling lifespan and stress resistance downstream of ALG-1. We found that upregulated ALG-1 is a shared feature in conditions linked to increased longevity (e.g., germline-deficient glp-1 mutants). ALG-1 knockdown reduces lifespan and oxidative stress resistance, while overexpression enhances survival against pro-oxidant agents but not heat or reductive stress. R02D3.7 represses alg-1 expression, impacting oxidative stress resistance at least in part via ALG-1. microRNAs upregulated in glp-1 mutants (miR-87-3p, miR-230-3p, and miR-235-3p) can target genes in the protein disulfide isomerase pathway and protect against oxidative stress. This study unveils a tightly regulated network involving transcription factors and microRNAs which controls organisms’ ability to withstand oxidative stress.
Project description:We aimed to characterize the cell-type specific loading patterns of miRNAs in c.elegans. We expressed cell-type specific HA-epitope tagged versions of Argonaute-like 1 (ALG-1) and ALG-2 from three major tissue types i.e. intestine, nervous system and body wall mucle. We found that most miRNAs display highly cell-type specific loading patterns. ALG-1 is more ubiquitously loaded whereas ALG-2 is eniriched for miRNA loading within the nervous system. Addtionally we show that there is flexibility in ALG loading which changes during the aging process.
Project description:Here, we report a new phosphorylation site on ALG-1 that modulates its ability to bind miRNAs. Mutating ALG-1 S642 into a phosphomimetic residue strongly impairs binding to miRNAs. Furthermore, this mutation causes embryonic lethality which are not observed in animals depleted of alg-1 suggesting that it may consequently impair the normal function of its homolog alg-2. Quantification of miRNAs in the phosphorylation mutants of alg-1 reveals that the miRNA passenger strands are strongly increased but not preferentially loaded into ALG-1, indicating that the defects in miRNA binding may also lead to an accumulation of miRNA duplexes.
Project description:MicroRNAs (miRNAs) are essential regulators involved in multiple biological processes. To achieve their gene repression function, they are loaded in miRNA-specific Argonautes to form the miRNA-induced silencing complex (miRISC). Mammals and C. elegans possess more than one paralog of miRNA-specific Argonautes but the dynamic between them remains unclear. Here, we report the conserved dipeptidyl peptidase DPF-3 as a new interactor of the miRNA-specific Argonautes ALG-1 and ALG-2 in C. elegans. Knockout of dpf-3 increases ALG-2 levels and miRISC formation in alg-1 null animals, thereby compensating for ALG-1 loss and rescuing miRNA-related defects observed. DPF-3 can cleave an ALG-2 N-terminal peptide in vitro but does not appear to rely on this catalytic activity to regulate ALG-2 in vivo. This study uncovers the importance of DPF-3 in the miRNA pathway and provides insights on how multiple miRNA Argonautes contribute to achieve proper miRNA-mediated gene regulation in animals.
Project description:Proctor2017 - Identifying microRNA for muscle regeneration during ageing (Mir1_in_muscle)
This model is described in the article:
Using computer simulation
models to investigate the most promising microRNAs to improve
muscle regeneration during ageing
Carole J. Proctor & Katarzyna
Goljanek-Whysall
Nature Scientific Reports
Abstract:
MicroRNAs (miRNAs) regulate gene expression through
interactions with target sites within mRNAs, leading to
enhanced degradation of the mRNA or inhibition of translation.
Skeletal muscle expresses many different miRNAs with important
roles in adulthood myogenesis (regeneration) and myofibre
hypertrophy and atrophy, processes associated with muscle
ageing. However, the large number of miRNAs and their targets
mean that a complex network of pathways exists, making it
difficult to predict the effect of selected miRNAs on
age-related muscle wasting. Computational modelling has the
potential to aid this process as it is possible to combine
models of individual miRNA:target interactions to form an
integrated network. As yet, no models of these interactions in
muscle exist. We created the first model of miRNA:target
interactions in myogenesis based on experimental evidence of
individual miRNAs which were next validated and used to make
testable predictions. Our model confirms that miRNAs regulate
key interactions during myogenesis and can act by promoting the
switch between quiescent/proliferating/differentiating
myoblasts and by maintaining the differentiation process. We
propose that a threshold level of miR-1 acts in the initial
switch to differentiation, with miR-181 keeping the switch on
and miR-378 maintaining the differentiation and miR-143
inhibiting myogenesis.
This model is hosted on
BioModels Database
and identified by:
MODEL1704110000.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:Proctor2017 - Identifying microRNA for muscle
regeneration during ageing (Mir181_in_muscle)
This model is described in the article:
Using computer simulation
models to investigate the most promising microRNAs to improve
muscle regeneration during ageing
Carole J. Proctor & Katarzyna
Goljanek-Whysall
Scientific Reports
Abstract:
MicroRNAs (miRNAs) regulate gene expression through
interactions with target sites within mRNAs, leading to
enhanced degradation of the mRNA or inhibition of translation.
Skeletal muscle expresses many different miRNAs with important
roles in adulthood myogenesis (regeneration) and myofibre
hypertrophy and atrophy, processes associated with muscle
ageing. However, the large number of miRNAs and their targets
mean that a complex network of pathways exists, making it
difficult to predict the effect of selected miRNAs on
age-related muscle wasting. Computational modelling has the
potential to aid this process as it is possible to combine
models of individual miRNA:target interactions to form an
integrated network. As yet, no models of these interactions in
muscle exist. We created the first model of miRNA:target
interactions in myogenesis based on experimental evidence of
individual miRNAs which were next validated and used to make
testable predictions. Our model confirms that miRNAs regulate
key interactions during myogenesis and can act by promoting the
switch between quiescent/proliferating/differentiating
myoblasts and by maintaining the differentiation process. We
propose that a threshold level of miR-1 acts in the initial
switch to differentiation, with miR-181 keeping the switch on
and miR-378 maintaining the differentiation and miR-143
inhibiting myogenesis.
This model is hosted on
BioModels Database
and identified by:
MODEL1704110001.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:Proctor2017 - Identifying microRNA for muscle regeneration during ageing (Mir378_in_muscle)
This model is described in the article:
Using computer simulation
models to investigate the most promising microRNAs to improve
muscle regeneration during ageing
Carole J. Proctor & Katarzyna
Goljanek-Whysall
Scientific Reports
Abstract:
MicroRNAs (miRNAs) regulate gene expression through
interactions with target sites within mRNAs, leading to
enhanced degradation of the mRNA or inhibition of translation.
Skeletal muscle expresses many different miRNAs with important
roles in adulthood myogenesis (regeneration) and myofibre
hypertrophy and atrophy, processes associated with muscle
ageing. However, the large number of miRNAs and their targets
mean that a complex network of pathways exists, making it
difficult to predict the effect of selected miRNAs on
age-related muscle wasting. Computational modelling has the
potential to aid this process as it is possible to combine
models of individual miRNA:target interactions to form an
integrated network. As yet, no models of these interactions in
muscle exist. We created the first model of miRNA:target
interactions in myogenesis based on experimental evidence of
individual miRNAs which were next validated and used to make
testable predictions. Our model confirms that miRNAs regulate
key interactions during myogenesis and can act by promoting the
switch between quiescent/proliferating/differentiating
myoblasts and by maintaining the differentiation process. We
propose that a threshold level of miR-1 acts in the initial
switch to differentiation, with miR-181 keeping the switch on
and miR-378 maintaining the differentiation and miR-143
inhibiting myogenesis.
This model is hosted on
BioModels Database
and identified by:
MODEL1704110002.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:Proctor2017 - Identifying microRNA for muscle
regeneration during ageing (Mir143_in_muscle)
This model is described in the article:
Using computer simulation
models to investigate the most promising microRNAs to improve
muscle regeneration during ageing
Carole J. Proctor & Katarzyna
Goljanek-Whysall
Scientific Reports
Abstract:
MicroRNAs (miRNAs) regulate gene expression through
interactions with target sites within mRNAs, leading to
enhanced degradation of the mRNA or inhibition of translation.
Skeletal muscle expresses many different miRNAs with important
roles in adulthood myogenesis (regeneration) and myofibre
hypertrophy and atrophy, processes associated with muscle
ageing. However, the large number of miRNAs and their targets
mean that a complex network of pathways exists, making it
difficult to predict the effect of selected miRNAs on
age-related muscle wasting. Computational modelling has the
potential to aid this process as it is possible to combine
models of individual miRNA:target interactions to form an
integrated network. As yet, no models of these interactions in
muscle exist. We created the first model of miRNA:target
interactions in myogenesis based on experimental evidence of
individual miRNAs which were next validated and used to make
testable predictions. Our model confirms that miRNAs regulate
key interactions during myogenesis and can act by promoting the
switch between quiescent/proliferating/differentiating
myoblasts and by maintaining the differentiation process. We
propose that a threshold level of miR-1 acts in the initial
switch to differentiation, with miR-181 keeping the switch on
and miR-378 maintaining the differentiation and miR-143
inhibiting myogenesis.
This model is hosted on
BioModels Database
and identified by:
MODEL1704110003.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.
Project description:Proctor2017 - Identifying microRNA for muscle
regeneration during ageing (Mirs_in_muscle)
This model is described in the article:
Using computer simulation
models to investigate the most promising microRNAs to improve
muscle regeneration during ageing
Carole J. Proctor & Katarzyna
Goljanek-Whysall
Nature Scientific Reports
Abstract:
MicroRNAs (miRNAs) regulate gene expression through
interactions with target sites within mRNAs, leading to
enhanced degradation of the mRNA or inhibition of translation.
Skeletal muscle expresses many different miRNAs with important
roles in adulthood myogenesis (regeneration) and myofibre
hypertrophy and atrophy, processes associated with muscle
ageing. However, the large number of miRNAs and their targets
mean that a complex network of pathways exists, making it
difficult to predict the effect of selected miRNAs on
age-related muscle wasting. Computational modelling has the
potential to aid this process as it is possible to combine
models of individual miRNA:target interactions to form an
integrated network. As yet, no models of these interactions in
muscle exist. We created the first model of miRNA:target
interactions in myogenesis based on experimental evidence of
individual miRNAs which were next validated and used to make
testable predictions. Our model confirms that miRNAs regulate
key interactions during myogenesis and can act by promoting the
switch between quiescent/proliferating/differentiating
myoblasts and by maintaining the differentiation process. We
propose that a threshold level of miR-1 acts in the initial
switch to differentiation, with miR-181 keeping the switch on
and miR-378 maintaining the differentiation and miR-143
inhibiting myogenesis.
This model is hosted on
BioModels Database
and identified by:
MODEL1704110004.
To cite BioModels Database, please use:
Chelliah V et al. BioModels: ten-year
anniversary. Nucl. Acids Res. 2015, 43(Database
issue):D542-8.
To the extent possible under law, all copyright and related or
neighbouring rights to this encoded model have been dedicated to
the public domain worldwide. Please refer to
CC0
Public Domain Dedication for more information.