Limits...
Ectopic hbox12 Expression Evoked by Histone Deacetylase Inhibition Disrupts Axial Specification of the Sea Urchin Embryo.

Cavalieri V, Spinelli G - PLoS ONE (2015)

Bottom Line: Transcription of nodal concomitantly drops, prejudicing dorsal/ventral polarity of the resulting larvae.Remarkably, impairing hbox12 function, either in a spatially-restricted sector or in the whole embryo, specifically rescues nodal transcription in Trichostatin-A-treated larvae.Beyond strengthen the notion that nodal expression is not allowed in the presence of functional Hbox12 in the same cells, these results highlight a critical role of histone deacetylases in regulating the spatial expression of hbox12.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Italy.

ABSTRACT
Dorsal/ventral patterning of the sea urchin embryo depends upon the establishment of a Nodal-expressing ventral organizer. Recently, we showed that spatial positioning of this organizer relies on the dorsal-specific transcription of the Hbox12 repressor. Building on these findings, we determined the influence of the epigenetic milieu on the expression of hbox12 and nodal genes. We find that Trichostatin-A, a potent and selective histone-deacetylases inhibitor, induces histone hyperacetylation in hbox12 chromatin, evoking broad ectopic expression of the gene. Transcription of nodal concomitantly drops, prejudicing dorsal/ventral polarity of the resulting larvae. Remarkably, impairing hbox12 function, either in a spatially-restricted sector or in the whole embryo, specifically rescues nodal transcription in Trichostatin-A-treated larvae. Beyond strengthen the notion that nodal expression is not allowed in the presence of functional Hbox12 in the same cells, these results highlight a critical role of histone deacetylases in regulating the spatial expression of hbox12.

Show MeSH

Related in: MedlinePlus

Effect of HDAC inhibition on the expression of the hbox12 gene.(A) P. lividus embryos cultured in the absence or in the presence of either TSA or VPA at the indicated dosages, and observed at the early blastula stage. (B) Northern blot analysis of total RNA isolated from embryos at the early blastula stage treated or not treated with TSA or VPA, and probed with an antisense 32P labelled RNA against the hbox12 transcript. The lower panel shows the loading control ribosomal RNAs in the ethidium bromide stained agarose gel. (C) qPCR measurements of hbox12 transcript abundance in blastulae treated with 50 nM TSA. Data are shown as normalized ΔCt (ΔΔCt, left ordinate), and as the corresponding fold difference in transcript abundance (right ordinate), with respect to control unperturbed embryos at the same stages of development. The gray region represents ΔΔCt values corresponding to less than 3-fold difference. Error bars are standard errors for the qPCR replicates. Oligonucleotide primer pairs used for qPCR reactions and amplicon lengths are indicated in the S1 Table. (D) Spatial distribution of the hbox12 transcripts in control and TSA-treated embryos at the early blastula stage, revealed by chromogenic WMISH.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4664418&req=5

pone.0143860.g001: Effect of HDAC inhibition on the expression of the hbox12 gene.(A) P. lividus embryos cultured in the absence or in the presence of either TSA or VPA at the indicated dosages, and observed at the early blastula stage. (B) Northern blot analysis of total RNA isolated from embryos at the early blastula stage treated or not treated with TSA or VPA, and probed with an antisense 32P labelled RNA against the hbox12 transcript. The lower panel shows the loading control ribosomal RNAs in the ethidium bromide stained agarose gel. (C) qPCR measurements of hbox12 transcript abundance in blastulae treated with 50 nM TSA. Data are shown as normalized ΔCt (ΔΔCt, left ordinate), and as the corresponding fold difference in transcript abundance (right ordinate), with respect to control unperturbed embryos at the same stages of development. The gray region represents ΔΔCt values corresponding to less than 3-fold difference. Error bars are standard errors for the qPCR replicates. Oligonucleotide primer pairs used for qPCR reactions and amplicon lengths are indicated in the S1 Table. (D) Spatial distribution of the hbox12 transcripts in control and TSA-treated embryos at the early blastula stage, revealed by chromogenic WMISH.

Mentions: To investigate whether histone acetylation is involved in the activation of hbox12 gene expression during sea urchin development, Paracentrotus lividus embryos were cultured in the presence of the HDAC inhibitors TSA or valproic acid (VPA). Treatment started from fertilization at concentrations of 50 nM and 5 mM, respectively. At these dosages, that are commensurate with effective doses determined in studies in mammalian systems [39,40], the rate of cell division was not altered, and embryos cleaved synchronously with respect to untreated controls (Fig 1A).


Ectopic hbox12 Expression Evoked by Histone Deacetylase Inhibition Disrupts Axial Specification of the Sea Urchin Embryo.

Cavalieri V, Spinelli G - PLoS ONE (2015)

Effect of HDAC inhibition on the expression of the hbox12 gene.(A) P. lividus embryos cultured in the absence or in the presence of either TSA or VPA at the indicated dosages, and observed at the early blastula stage. (B) Northern blot analysis of total RNA isolated from embryos at the early blastula stage treated or not treated with TSA or VPA, and probed with an antisense 32P labelled RNA against the hbox12 transcript. The lower panel shows the loading control ribosomal RNAs in the ethidium bromide stained agarose gel. (C) qPCR measurements of hbox12 transcript abundance in blastulae treated with 50 nM TSA. Data are shown as normalized ΔCt (ΔΔCt, left ordinate), and as the corresponding fold difference in transcript abundance (right ordinate), with respect to control unperturbed embryos at the same stages of development. The gray region represents ΔΔCt values corresponding to less than 3-fold difference. Error bars are standard errors for the qPCR replicates. Oligonucleotide primer pairs used for qPCR reactions and amplicon lengths are indicated in the S1 Table. (D) Spatial distribution of the hbox12 transcripts in control and TSA-treated embryos at the early blastula stage, revealed by chromogenic WMISH.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4664418&req=5

pone.0143860.g001: Effect of HDAC inhibition on the expression of the hbox12 gene.(A) P. lividus embryos cultured in the absence or in the presence of either TSA or VPA at the indicated dosages, and observed at the early blastula stage. (B) Northern blot analysis of total RNA isolated from embryos at the early blastula stage treated or not treated with TSA or VPA, and probed with an antisense 32P labelled RNA against the hbox12 transcript. The lower panel shows the loading control ribosomal RNAs in the ethidium bromide stained agarose gel. (C) qPCR measurements of hbox12 transcript abundance in blastulae treated with 50 nM TSA. Data are shown as normalized ΔCt (ΔΔCt, left ordinate), and as the corresponding fold difference in transcript abundance (right ordinate), with respect to control unperturbed embryos at the same stages of development. The gray region represents ΔΔCt values corresponding to less than 3-fold difference. Error bars are standard errors for the qPCR replicates. Oligonucleotide primer pairs used for qPCR reactions and amplicon lengths are indicated in the S1 Table. (D) Spatial distribution of the hbox12 transcripts in control and TSA-treated embryos at the early blastula stage, revealed by chromogenic WMISH.
Mentions: To investigate whether histone acetylation is involved in the activation of hbox12 gene expression during sea urchin development, Paracentrotus lividus embryos were cultured in the presence of the HDAC inhibitors TSA or valproic acid (VPA). Treatment started from fertilization at concentrations of 50 nM and 5 mM, respectively. At these dosages, that are commensurate with effective doses determined in studies in mammalian systems [39,40], the rate of cell division was not altered, and embryos cleaved synchronously with respect to untreated controls (Fig 1A).

Bottom Line: Transcription of nodal concomitantly drops, prejudicing dorsal/ventral polarity of the resulting larvae.Remarkably, impairing hbox12 function, either in a spatially-restricted sector or in the whole embryo, specifically rescues nodal transcription in Trichostatin-A-treated larvae.Beyond strengthen the notion that nodal expression is not allowed in the presence of functional Hbox12 in the same cells, these results highlight a critical role of histone deacetylases in regulating the spatial expression of hbox12.

View Article: PubMed Central - PubMed

Affiliation: Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Italy.

ABSTRACT
Dorsal/ventral patterning of the sea urchin embryo depends upon the establishment of a Nodal-expressing ventral organizer. Recently, we showed that spatial positioning of this organizer relies on the dorsal-specific transcription of the Hbox12 repressor. Building on these findings, we determined the influence of the epigenetic milieu on the expression of hbox12 and nodal genes. We find that Trichostatin-A, a potent and selective histone-deacetylases inhibitor, induces histone hyperacetylation in hbox12 chromatin, evoking broad ectopic expression of the gene. Transcription of nodal concomitantly drops, prejudicing dorsal/ventral polarity of the resulting larvae. Remarkably, impairing hbox12 function, either in a spatially-restricted sector or in the whole embryo, specifically rescues nodal transcription in Trichostatin-A-treated larvae. Beyond strengthen the notion that nodal expression is not allowed in the presence of functional Hbox12 in the same cells, these results highlight a critical role of histone deacetylases in regulating the spatial expression of hbox12.

Show MeSH
Related in: MedlinePlus