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Distinct functional and temporal requirements for zebrafish Hdac1 during neural crest-derived craniofacial and peripheral neuron development.

Ignatius MS, Unal Eroglu A, Malireddy S, Gallagher G, Nambiar RM, Henion PD - PLoS ONE (2013)

Bottom Line: In the peripheral nervous system, there is a disruption of enteric, DRG and sympathetic neuron differentiation in hdac1(b382) mutants compared to wildtype embryos.Sympathetic neuron precursors are specified in hdac1(b382) mutants and they undergo generic neuronal differentiation but fail to undergo noradrenergic differentiation.Using the HDAC inhibitor TSA, we isolated enzyme activity and temporal requirements for HDAC function that reproduce hdac1(b382) defects in craniofacial and sympathetic neuron development.

View Article: PubMed Central - PubMed

Affiliation: Molecular, Cellular and Developmental Biology Program, Ohio State University, Columbus, Ohio, United States of America.

ABSTRACT
The regulation of gene expression is accomplished by both genetic and epigenetic means and is required for the precise control of the development of the neural crest. In hdac1(b382) mutants, craniofacial cartilage development is defective in two distinct ways. First, fewer hoxb3a, dlx2 and dlx3-expressing posterior branchial arch precursors are specified and many of those that are consequently undergo apoptosis. Second, in contrast, normal numbers of progenitors are present in the anterior mandibular and hyoid arches, but chondrocyte precursors fail to terminally differentiate. In the peripheral nervous system, there is a disruption of enteric, DRG and sympathetic neuron differentiation in hdac1(b382) mutants compared to wildtype embryos. Specifically, enteric and DRG-precursors differentiate into neurons in the anterior gut and trunk respectively, while enteric and DRG neurons are rarely present in the posterior gut and tail. Sympathetic neuron precursors are specified in hdac1(b382) mutants and they undergo generic neuronal differentiation but fail to undergo noradrenergic differentiation. Using the HDAC inhibitor TSA, we isolated enzyme activity and temporal requirements for HDAC function that reproduce hdac1(b382) defects in craniofacial and sympathetic neuron development. Our study reveals distinct functional and temporal requirements for zebrafish hdac1 during neural crest-derived craniofacial and peripheral neuron development.

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Effect of HDAC inhibition on sympathetic neuron differentiation is reversible.A, B wild-type embryos treated with DMSO (A) and TSA (B) continuously from 28–52 hpf and then fixed at 52 hpf and stained for th expression, black arrowheads indicate sympathetic neurons. C–E wild-type embryos treated under three different conditions, C with DMSO between 28–72 hpf, D with TSA between 28–72 hpf, and E with TSA between 28–52 hpf after which the TSA is washed out and then the embryos are treated in DMSO between 52–72 hpf. All embryos were fixed at 72 hpf and then stained for th expression. Black arrowheads indicate th-xpressing sympathetic neurons, or their absence.
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pone-0063218-g007: Effect of HDAC inhibition on sympathetic neuron differentiation is reversible.A, B wild-type embryos treated with DMSO (A) and TSA (B) continuously from 28–52 hpf and then fixed at 52 hpf and stained for th expression, black arrowheads indicate sympathetic neurons. C–E wild-type embryos treated under three different conditions, C with DMSO between 28–72 hpf, D with TSA between 28–72 hpf, and E with TSA between 28–52 hpf after which the TSA is washed out and then the embryos are treated in DMSO between 52–72 hpf. All embryos were fixed at 72 hpf and then stained for th expression. Black arrowheads indicate th-xpressing sympathetic neurons, or their absence.

Mentions: Disruption of Hdac1 function in hdac1b382 mutants results in the failure of the noradrenergic differentiation of sympathetic neurons based on the absence of th and dbh expression even though sympathoadrenergic precursors cells are present, and many of which undergo generic neuronal differentiation. We therefore assessed the effect of TSA-induced HDAC inhibition on noradrenergic differentiation of sympathetic neurons by testing the effect of 800 nM TSA on th expression in sympathetic neurons (Table 3). Treatment of wildtype embryos for 24 h between 28–52 hpf results in the complete absence of th-expression in sympathetic ganglia (0%, n = 82, Fig. 7 A, B). In contrast to sympathetic neuron th-expression, TSA-treated embryos retain th-expression in non-neural crest-derived midbrain dopaminergic neurons and arch associated ganglia (100% and 98.8% of treated embryos respectively, n = 82). All wildtype control (DMSO treated) embryos expressed th in the sympathetic ganglia, midbrain dopaminergic neurons and arch associated ganglia (n = 140). In hdac1b382 mutants, sympathetic neuron precursors express phox2b and zash1a. We therefore analyzed phox2b expression in 28–52 hpf 800 nM TSA-treated embryos. 95% (n = 78) of all TSA treated wildtype embryos express phox2b in the sympathetic ganglia at 52 hpf, even though qualitatively, the overall ganglia size is slightly reduced when compared to control DMSO-treated wild-type embryos (Figure S1). These data indicate that treatment of wild-type embryos for 24 h between 28–52 hpf results in defects in noradrenergic differentiation of sympathetic neurons similar to hdac1b382 mutants. These results also indicate that the effect of HDAC inhibition on th expression is cell type specific with midbrain dopaminergic neurons and arch associated ganglia th-expression relatively unaffected by TSA, compared to neural crest-derived sympathetic neurons.


Distinct functional and temporal requirements for zebrafish Hdac1 during neural crest-derived craniofacial and peripheral neuron development.

Ignatius MS, Unal Eroglu A, Malireddy S, Gallagher G, Nambiar RM, Henion PD - PLoS ONE (2013)

Effect of HDAC inhibition on sympathetic neuron differentiation is reversible.A, B wild-type embryos treated with DMSO (A) and TSA (B) continuously from 28–52 hpf and then fixed at 52 hpf and stained for th expression, black arrowheads indicate sympathetic neurons. C–E wild-type embryos treated under three different conditions, C with DMSO between 28–72 hpf, D with TSA between 28–72 hpf, and E with TSA between 28–52 hpf after which the TSA is washed out and then the embryos are treated in DMSO between 52–72 hpf. All embryos were fixed at 72 hpf and then stained for th expression. Black arrowheads indicate th-xpressing sympathetic neurons, or their absence.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3646935&req=5

pone-0063218-g007: Effect of HDAC inhibition on sympathetic neuron differentiation is reversible.A, B wild-type embryos treated with DMSO (A) and TSA (B) continuously from 28–52 hpf and then fixed at 52 hpf and stained for th expression, black arrowheads indicate sympathetic neurons. C–E wild-type embryos treated under three different conditions, C with DMSO between 28–72 hpf, D with TSA between 28–72 hpf, and E with TSA between 28–52 hpf after which the TSA is washed out and then the embryos are treated in DMSO between 52–72 hpf. All embryos were fixed at 72 hpf and then stained for th expression. Black arrowheads indicate th-xpressing sympathetic neurons, or their absence.
Mentions: Disruption of Hdac1 function in hdac1b382 mutants results in the failure of the noradrenergic differentiation of sympathetic neurons based on the absence of th and dbh expression even though sympathoadrenergic precursors cells are present, and many of which undergo generic neuronal differentiation. We therefore assessed the effect of TSA-induced HDAC inhibition on noradrenergic differentiation of sympathetic neurons by testing the effect of 800 nM TSA on th expression in sympathetic neurons (Table 3). Treatment of wildtype embryos for 24 h between 28–52 hpf results in the complete absence of th-expression in sympathetic ganglia (0%, n = 82, Fig. 7 A, B). In contrast to sympathetic neuron th-expression, TSA-treated embryos retain th-expression in non-neural crest-derived midbrain dopaminergic neurons and arch associated ganglia (100% and 98.8% of treated embryos respectively, n = 82). All wildtype control (DMSO treated) embryos expressed th in the sympathetic ganglia, midbrain dopaminergic neurons and arch associated ganglia (n = 140). In hdac1b382 mutants, sympathetic neuron precursors express phox2b and zash1a. We therefore analyzed phox2b expression in 28–52 hpf 800 nM TSA-treated embryos. 95% (n = 78) of all TSA treated wildtype embryos express phox2b in the sympathetic ganglia at 52 hpf, even though qualitatively, the overall ganglia size is slightly reduced when compared to control DMSO-treated wild-type embryos (Figure S1). These data indicate that treatment of wild-type embryos for 24 h between 28–52 hpf results in defects in noradrenergic differentiation of sympathetic neurons similar to hdac1b382 mutants. These results also indicate that the effect of HDAC inhibition on th expression is cell type specific with midbrain dopaminergic neurons and arch associated ganglia th-expression relatively unaffected by TSA, compared to neural crest-derived sympathetic neurons.

Bottom Line: In the peripheral nervous system, there is a disruption of enteric, DRG and sympathetic neuron differentiation in hdac1(b382) mutants compared to wildtype embryos.Sympathetic neuron precursors are specified in hdac1(b382) mutants and they undergo generic neuronal differentiation but fail to undergo noradrenergic differentiation.Using the HDAC inhibitor TSA, we isolated enzyme activity and temporal requirements for HDAC function that reproduce hdac1(b382) defects in craniofacial and sympathetic neuron development.

View Article: PubMed Central - PubMed

Affiliation: Molecular, Cellular and Developmental Biology Program, Ohio State University, Columbus, Ohio, United States of America.

ABSTRACT
The regulation of gene expression is accomplished by both genetic and epigenetic means and is required for the precise control of the development of the neural crest. In hdac1(b382) mutants, craniofacial cartilage development is defective in two distinct ways. First, fewer hoxb3a, dlx2 and dlx3-expressing posterior branchial arch precursors are specified and many of those that are consequently undergo apoptosis. Second, in contrast, normal numbers of progenitors are present in the anterior mandibular and hyoid arches, but chondrocyte precursors fail to terminally differentiate. In the peripheral nervous system, there is a disruption of enteric, DRG and sympathetic neuron differentiation in hdac1(b382) mutants compared to wildtype embryos. Specifically, enteric and DRG-precursors differentiate into neurons in the anterior gut and trunk respectively, while enteric and DRG neurons are rarely present in the posterior gut and tail. Sympathetic neuron precursors are specified in hdac1(b382) mutants and they undergo generic neuronal differentiation but fail to undergo noradrenergic differentiation. Using the HDAC inhibitor TSA, we isolated enzyme activity and temporal requirements for HDAC function that reproduce hdac1(b382) defects in craniofacial and sympathetic neuron development. Our study reveals distinct functional and temporal requirements for zebrafish hdac1 during neural crest-derived craniofacial and peripheral neuron development.

Show MeSH
Related in: MedlinePlus