Eye-Specific Gene Expression following Embryonic Ethanol Exposure in Zebrafish: Roles for Heat Shock Factor 1
Ontology highlight
ABSTRACT: Ethanol is a well-known teratogen. While this teratogenic potential is well-characterized clinically, the mechanisms through which ethanol exposure results in developmental defects remain unclear. Here we use the zebrafish model to elucidate eye-specific mechanisms that may underlie ethanol-mediated microphthalmia (reduced eye size), using time-series microarray analysis of gene expression of eye tissues of embryos exposed to 1.5% ethanol vs. untreated embryos. We identified 62 genes differentially expressed in ethanol-treated as compared to control zebrafish eyes from all sampling times over the period of retinal neurogenesis (24-48 hours post-fertilization). Application of the EDGE (extraction of differential gene expression) algorithm identified over 3000 genes differentially expressed over developmental time in ethanol-treated embryo eyes as compared to untreated embryo eyes. These lists included several genes indicating a mis-regulated cellular stress response (heat shock response) due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino (MO) targeting heat shock factor 1 (hsf-1) mRNA resulted in a microphthalmic phenotype, suggesting convergent molecular pathways. Manipulation of the heat shock response by thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. Together these data are consistent with roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure in zebrafish. time series, 9 samples, no replicates
Project description:Ethanol is a well-known teratogen. While this teratogenic potential is well-characterized clinically, the mechanisms through which ethanol exposure results in developmental defects remain unclear. Here we use the zebrafish model to elucidate eye-specific mechanisms that may underlie ethanol-mediated microphthalmia (reduced eye size), using time-series microarray analysis of gene expression of eye tissues of embryos exposed to 1.5% ethanol vs. untreated embryos. We identified 62 genes differentially expressed in ethanol-treated as compared to control zebrafish eyes from all sampling times over the period of retinal neurogenesis (24-48 hours post-fertilization). Application of the EDGE (extraction of differential gene expression) algorithm identified over 3000 genes differentially expressed over developmental time in ethanol-treated embryo eyes as compared to untreated embryo eyes. These lists included several genes indicating a mis-regulated cellular stress response (heat shock response) due to ethanol exposure. Combined treatment with sub-threshold levels of ethanol and a morpholino (MO) targeting heat shock factor 1 (hsf-1) mRNA resulted in a microphthalmic phenotype, suggesting convergent molecular pathways. Manipulation of the heat shock response by thermal preconditioning partially prevented ethanol-mediated microphthalmia while maintaining Hsf-1 expression. Together these data are consistent with roles for reduced Hsf-1 in mediating microphthalmic effects of embryonic ethanol exposure in zebrafish.
Project description:Proctor2005 - Actions of chaperones and their
role in ageing
This model is described in the article:
Modelling the actions of
chaperones and their role in ageing.
Proctor CJ, Soti C, Boys RJ,
Gillespie CS, Shanley DP, Wilkinson DJ, Kirkwood TB.
Mech. Ageing Dev. 2005 Jan; 126(1):
119-131
Abstract:
Many molecular chaperones are also known as heat shock
proteins because they are synthesised in increased amounts
after brief exposure of cells to elevated temperatures. They
have many cellular functions and are involved in the folding of
nascent proteins, the re-folding of denatured proteins, the
prevention of protein aggregation, and assisting the targeting
of proteins for degradation by the proteasome and lysosomes.
They also have a role in apoptosis and are involved in
modulating signals for immune and inflammatory responses.
Stress-induced transcription of heat shock proteins requires
the activation of heat shock factor (HSF). Under normal
conditions, HSF is bound to heat shock proteins resulting in
feedback repression. During stress, cellular proteins undergo
denaturation and sequester heat shock proteins bound to HSF,
which is then able to become transcriptionally active. The
induction of heat shock proteins is impaired with age and there
is also a decline in chaperone function. Aberrant/damaged
proteins accumulate with age and are implicated in several
important age-related conditions (e.g. Alzheimer's disease,
Parkinson's disease, and cataract). Therefore, the balance
between damaged proteins and available free chaperones may be
greatly disturbed during ageing. We have developed a
mathematical model to describe the heat shock system. The aim
of the model is two-fold: to explore the heat shock system and
its implications in ageing; and to demonstrate how to build a
model of a biological system using our simulation system
(biology of ageing e-science integration and simulation
(BASIS)).
This model is hosted on
BioModels Database
and identified by:
BIOMD0000000091.
To cite BioModels Database, please use:
BioModels Database:
An enhanced, curated and annotated resource for published
quantitative kinetic models.
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:The goal of this RNA-Seq analysis was to identify genes differentially expressed in wild type (N2) and a hypomorphic mutant of the gene encoding heat shock factor 1 {hsf-1(sy441)} at normal conditions and upon heat shock. This study aimed to identify genes that are up- or downregulated when HSF-1 activity is impaired at 20 ºC. We also aimed to identify gene that are regulated by HSF-1 upon heat stress by comparing differentially expressed genes upon heat shock in wild type and in hsf-1(sy441) mutant background.
Project description:To understand the function and regulation of the C. elegans heat shock factor (HSF-1) in larval development, we have used ChIP-seq to analyze the occupancy of HSF1 and RNA Pol II in L2 larvae and young adult (YA) animals grown at 20°C or upon heat shock at 34°C for 30 min. In addition, we have used RNA-seq to analyze the transcriptomes of wild type (N2), hsf-1(ok600) mutants and hsf-1(ok600); rmSi1[hsf-1::gfp] L2 larvae grown at 20°C and characterized the gene expression change by heat shock in wild type (N2), hsf-1(sy441) and hsf-1(sy441);rmSi1[hsf-1::gfp] animals at L2 stage.
Project description:To understand the roles of HSF-1 and its regulation in reproduction and heat shock response in a tissue-specific manner, we coupled tissue-specific HSF-1 depletion in C. elegans by auxin-inducible degron (AID) with genome-wide transcriptional analyses in whole animals. We used ChIP-seq to analyze the occupancy of HSF-1 (tagged with AID::GFP) and RNA Pol II in young adult (YA) animals grown at 20°C or upon heat shock (HS) at 34°C for 30 min following an acute depletion of HSF-1 by AID for 2 hours either in the somatic or in the germline cells. Depletion by AID was performed by transferring worms expressing the E3 ligase TIR1 and carrying AID insertion to endogenous HSF-1 (JTL611 or JTL621) to NGM plates containing 1mM auxin (indole- 3-acetic acid, Sigma). The mock treatment was done by transferring worms to plates only containing the vehicle ethanol (EtOH). In parallel, we used RNA-seq to analyze the heat shock respnse upon depletion of HSF-1 in the soma or the germline for 2 hours. In addition, we also analyzed the transcriptomic changes by RNA-seq upon tissue-specific depletion of HSF-1 initiated at young adult stage for different length of time. In all RNA-seq analyses, we included the strains that only express TIR1 but do not have degron insertion at HSF-1 (CA1200 and CA1199) to control for the effects of auxin treatment and AID insertion into HSF-1.
Project description:To understand the roles of HSF-1 and its regulation in reproduction and heat shock response in a tissue-specific manner, we coupled tissue-specific HSF-1 depletion in C. elegans by auxin-inducible degron (AID) with genome-wide transcriptional analyses in whole animals. We used ChIP-seq to analyze the occupancy of HSF-1 (tagged with AID::GFP) and RNA Pol II in young adult (YA) animals grown at 20°C or upon heat shock (HS) at 34°C for 30 min following an acute depletion of HSF-1 by AID for 2 hours either in the somatic or in the germline cells. Depletion by AID was performed by transferring worms expressing the E3 ligase TIR1 and carrying AID insertion to endogenous HSF-1 (JTL611 or JTL621) to NGM plates containing 1mM auxin (indole- 3-acetic acid, Sigma). The mock treatment was done by transferring worms to plates only containing the vehicle ethanol (EtOH). In parallel, we used RNA-seq to analyze the heat shock respnse upon depletion of HSF-1 in the soma or the germline for 2 hours. In addition, we also analyzed the transcriptomic changes by RNA-seq upon tissue-specific depletion of HSF-1 initiated at young adult stage for different length of time. In all RNA-seq analyses, we included the strains that only express TIR1 but do not have degron insertion at HSF-1 (CA1200 and CA1199) to control for the effects of auxin treatment and AID insertion into HSF-1.
Project description:To understand the roles of HSF-1 and its regulation in reproduction and heat shock response in a tissue-specific manner, we coupled tissue-specific HSF-1 depletion in C. elegans by auxin-inducible degron (AID) with genome-wide transcriptional analyses in whole animals. We used ChIP-seq to analyze the occupancy of HSF-1 (tagged with AID::GFP) and RNA Pol II in young adult (YA) animals grown at 20°C or upon heat shock (HS) at 34°C for 30 min following an acute depletion of HSF-1 by AID for 2 hours either in the somatic or in the germline cells. Depletion by AID was performed by transferring worms expressing the E3 ligase TIR1 and carrying AID insertion to endogenous HSF-1 (JTL611 or JTL621) to NGM plates containing 1mM auxin (indole- 3-acetic acid, Sigma). The mock treatment was done by transferring worms to plates only containing the vehicle ethanol (EtOH). In parallel, we used RNA-seq to analyze the heat shock respnse upon depletion of HSF-1 in the soma or the germline for 2 hours. In addition, we also analyzed the transcriptomic changes by RNA-seq upon tissue-specific depletion of HSF-1 initiated at young adult stage for different length of time. In all RNA-seq analyses, we included the strains that only express TIR1 but do not have degron insertion at HSF-1 (CA1200 and CA1199) to control for the effects of auxin treatment and AID insertion into HSF-1.
Project description:To understand the function and regulation of the C. elegans heat shock factor (HSF-1) in larval development, we have used ChIP-seq to analyze the occupancy of HSF1 and RNA Pol II in L2 larvae and young adult (YA) animals grown at 20°C or upon heat shock at 34°C for 30 min. In addition, we have used RNA-seq to analyze the transcriptomes of wild type (N2), hsf-1(ok600) mutants and hsf-1(ok600); rmSi1[hsf-1::gfp] L2 larvae grown at 20°C and characterized the gene expression change by heat shock in wild type (N2) animals at L2 stage.
Project description:To understand the function and regulation of the C. elegans heat shock factor (HSF-1) in larval development, we have used ChIP-seq to analyze the occupancy of HSF1 and RNA Pol II in L2 larvae and young adult (YA) animals grown at 20°C or upon heat shock at 34°C for 30 min. In addition, we have used RNA-seq to analyze the transcriptomes of wild type (N2), hsf-1(ok600) mutants and hsf-1(ok600); rmSi1[hsf-1::gfp] L2 larvae grown at 20°C and characterized the gene expression change by heat shock in wild type (N2) animals at L2 stage.