Project description:MicroRNAs (miRNAs) are involved in the regulation of important biological processes. Here, we describe a novel Drosophila miRNAs involved in ageing. We selected eight Drosophila miRNAs, displaying high homology with seed sequences of ageing-related miRNAs characterized in other species, and investigated whether the overexpression of these miRNAs affected ageing in Drosophila adult flies. The lifespan of adults overexpressing miR-305, a miRNA showing high homology with miR-239 in C. elegans, was significantly shorter. Conversely, a reduction in miR-305 expression led to a longer lifespan than that in control flies. miR-305 overexpression accelerated the impairment of locomotor activity, and promoted the age-dependent accumulation of poly-ubiquitinated protein aggregates in the muscle, as flies aged. Thus, we demonstrate that the ectopic expression of miR-305 has a deleterious effect on ageing in Drosophila. To identify the targets of miR-305, we performed RNA-Seq. We discovered several mRNAs encoding antimicrobial peptides and insulin-like peptides, whose expression changed in adults upon miR-305 overexpression. We further confirmed, by qRT-PCR, that miR-305 overexpression significantly decreases the mRNA levels of four antimicrobial peptides. As these mRNAs contain multiple sequences matching the seed sequence of miR-305, we speculate that a reduction in target mRNA levels, caused by ectopic miRNA expression, promotes ageing.
Project description:RNA sequencing of Apis mellifera abdominal fat body and matched whole brain following a knockdown in fat body ame-miR-305-5p expression
Project description:MicroRNAs comprise 1-3% of all vertebrate genes, but their in vivo functions and mechanisms of action remain largely unknown. Zebrafish miR-430 is expressed at the onset of zygotic transcription and regulates morphogenesis during early development. Using a microarray approach and in vivo target validation, we find that miR-430 directly regulates several hundred target mRNAs. Targets are highly enriched for maternal mRNAs that accumulate in the absence of miR-430. We also show that miR-430 accelerates the deadenylation of target mRNAs. These results suggest that miR-430 facilitates the deadenylation and clearance of maternal mRNAs during early embryogenesis. Keywords: Dicer, MZdicer, miR-430, miRNA target, maternal, zygotic
Project description:MicroRNAs inhibit gene expression by recruiting the RNA-induced silencing complex (RISC) to mRNAs in a process termed RNA interference (RNAi). While it is generally accepted that RNAi modulates gene expression pervasively, the number of mRNAs bound and repressed by miRNAs in vivo in individual cell types remains unknown, with estimates ranging from a few hundred genes to many thousands. We examined microRNA activities in primary cells by combining genetic loss of function with RNA-sequencing, quantitative proteomics and High-Throughput Sequencing of RNA isolated by Crosslinking Immunoprecipitation (HITS-CLIP), focusing on miR-144/451, the most highly expressed microRNA locus during red blood cell (RBC) formation. We show that Argonaute (Ago) protein binds over one thousand different mRNAs in a miR-144/451-dependent manner, accounting for one third of all Ago-bound mRNAs. However, only about 100 mRNAs are stabilized in RBC precursors after ablation of the miR-144/451 locus. Thus, Ago-miRNA complexes destabilize only a small subset of bound mRNAs, probably no more than a few hundred in erythroblasts under physiological conditions. Our integrated approach identified more than 50 new miR-144/451 target mRNAs, including Cox10, which facilitates assembly of the mitochondrial cytochrome c oxidase (COX) electron transport complex. Loss of miR-144/451 resulted in increased Cox10 expression, accumulation of the COX complex, and increased mitochondrial membrane potential with no change in mitochondrial mass. Thus, miR-144/451 represses mitochondrial respiration during erythropoiesis by inhibiting Cox10.
Project description:MicroRNAs inhibit gene expression by recruiting the RNA-induced silencing complex (RISC) to mRNAs in a process termed RNA interference (RNAi). While it is generally accepted that RNAi modulates gene expression pervasively, the number of mRNAs bound and repressed by miRNAs in vivo in individual cell types remains unknown, with estimates ranging from a few hundred genes to many thousands. We examined microRNA activities in primary cells by combining genetic loss of function with RNA-sequencing, quantitative proteomics and High-Throughput Sequencing of RNA isolated by Crosslinking Immunoprecipitation (HITS-CLIP), focusing on miR-144/451, the most highly expressed microRNA locus during red blood cell (RBC) formation. We show that Argonaute (Ago) protein binds over one thousand different mRNAs in a miR-144/451-dependent manner, accounting for one third of all Ago-bound mRNAs. However, only about 100 mRNAs are stabilized in RBC precursors after ablation of the miR-144/451 locus. Thus, Ago-miRNA complexes destabilize only a small subset of bound mRNAs, probably no more than a few hundred in erythroblasts under physiological conditions. Our integrated approach identified more than 50 new miR-144/451 target mRNAs, including Cox10, which facilitates assembly of the mitochondrial cytochrome c oxidase (COX) electron transport complex. Loss of miR-144/451 resulted in increased Cox10 expression, accumulation of the COX complex, and increased mitochondrial membrane potential with no change in mitochondrial mass. Thus, miR-144/451 represses mitochondrial respiration during erythropoiesis by inhibiting Cox10.
Project description:MicroRNAs inhibit gene expression by recruiting the RNA-induced silencing complex (RISC) to mRNAs in a process termed RNA interference (RNAi). While it is generally accepted that RNAi modulates gene expression pervasively, the number of mRNAs bound and repressed by miRNAs in vivo in individual cell types remains unknown, with estimates ranging from a few hundred genes to many thousands. We examined microRNA activities in primary cells by combining genetic loss of function with RNA-sequencing, quantitative proteomics and High-Throughput Sequencing of RNA isolated by Crosslinking Immunoprecipitation (HITS-CLIP), focusing on miR-144/451, the most highly expressed microRNA locus during red blood cell (RBC) formation. We show that Argonaute (Ago) protein binds over one thousand different mRNAs in a miR-144/451-dependent manner, accounting for one third of all Ago-bound mRNAs. However, only about 100 mRNAs are stabilized in RBC precursors after ablation of the miR-144/451 locus. Thus, Ago-miRNA complexes destabilize only a small subset of bound mRNAs, probably no more than a few hundred in erythroblasts under physiological conditions. Our integrated approach identified more than 50 new miR-144/451 target mRNAs, including Cox10, which facilitates assembly of the mitochondrial cytochrome c oxidase (COX) electron transport complex. Loss of miR-144/451 resulted in increased Cox10 expression, accumulation of the COX complex, and increased mitochondrial membrane potential with no change in mitochondrial mass. Thus, miR-144/451 represses mitochondrial respiration during erythropoiesis by inhibiting Cox10.
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.