Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development. Four tissue types: 2, 4, 6, and 9 hours post fertilzation embryos. Two treatments: Untreated (WT), and Retinoic Acid treated embryos(RA).
Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development. Expression of embronic transcripts were used to determine expressed and non-expressed gene groups for further chromatin studies.
Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development.
Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development.
Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development.
Project description:Nucleosome arrangement in promoter regions has been shown to play an important role in gene regulation. Genome wide studies in yeast, flies, worms, mammalian ES and transformed cell lines have found well positioned nucleosomes with an area of nucleosome depletion flanking transcription start sites. This Nucleosome arrangement has been shown to be dependent on sequence (cis-regulatory factors), DNA binding factors (trans-regulatory factors) and ATP-dependant chromatin modifiers. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome undergoes a whole scale rechromatinization event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development we map nucleosome positions at the promoter region of 34 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a dynamic process which happens over several stages. We also find evidence that trans-regulatory factors play a greater role in nucleosome positioning over cis-regulatory elements. Finally we provide evidence that transcriptional activation is the driving force behind the arrangement of nucleosomes at the promoters of hox gene during early development. Five tissue types: 2, 4, 6, and 9 hours post fertilzation embryos and ZF4 cell line. Three treatments: Untreated (WT), Retinoic Acid treated embryos (RA), DEAB treated embryos. Two biological replicates for DNA input samples.
Project description:Purpose: Construction of 3D zebrafish spatial transcriptomics data for studying the establishment of AP axis. Methods: We performed serial bulk RNA-seq data of zebrafish embryo at three development points. Using the published spatial transcriptomics data as references, we implemented Palette to infer spatial gene expression from bulk RNA-seq data and constructed 3D embryonic spatial transcriptomics. The constructed 3D transcriptomics data was then projected on zebrafish embryo images with 3D coordinates, establishing a spatial gene expression atlas named Danio rerio Asymmetrical Maps (DreAM). Results: DreAM provides a powerful platform for visualizing gene expression patterns on zebrafish morphology and investigating spatial cell-cell interactions. Conclusions: Our work used DreAM to explore the establishment of anteroposterior (AP) axis, and identified multiple morphogen gradients that played essential roles in determining cell AP positions. Finally, we difined a hox score, and comprehensively demonstrated the spatial collinearity of Hox genes at single-cell resolution during development.
Project description:We have used micrococcal nuclease (MNase) digestion followed by deep sequencing in order to obtain a higher-resolution map than previously available of nucleosome positions in the fission yeast, Schizosaccharomyces pombe. Our data confirm an unusually short average nucleosome repeat length, ~152 bp, in fission yeast and that transcriptional start sites (TSSs) are associated with nucleosome-depleted regions (NDRs), ordered nucleosome arrays downstream and less regularly spaced upstream nucleosomes. In addition, we found enrichments for associated function in four of eight groups of genes clustered according to chromatin configurations near TSSs. At replication origins, our data revealed asymmetric localization of Pre-Replication Complex (pre-RC) proteins within large NDRsM-bM-^@M-^Ta feature that is conserved in fission and budding yeast and is therefore likely to be conserved in other eukaryotic organisms. Examination of nucleosome positioning in Schizosaccharomyces pombe