Prdm1- and Sox6-mediated transcriptional repression specifies muscle fibre type in the zebrafish embryo.
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ABSTRACT:
SUBMITTER: von Hofsten J
PROVIDER: S-EPMC2424280 | biostudies-literature | 2008 Jul
REPOSITORIES: biostudies-literature
Publications
Prdm1- and Sox6-mediated transcriptional repression specifies muscle fibre type in the zebrafish embryo.
von Hofsten Jonas J Elworthy Stone S Gilchrist Michael J MJ Smith James C JC Wardle Fiona C FC Ingham Philip W PW
EMBO reports 20080606 7
The zebrafish u-boot (ubo) gene encodes the transcription factor Prdm1, which is essential for the specification of the primary slow-twitch muscle fibres that derive from adaxial cells. Here, we show that Prdm1 functions by acting as a transcriptional repressor and that slow-twitch-specific muscle gene expression is activated by Prdm1-mediated repression of the transcriptional repressor Sox6. Genes encoding fast-specific isoforms of sarcomeric proteins are ectopically expressed in the adaxial ce ...[more]
Similar Datasets
Project description:The zebrafish u-boot (ubo) gene encodes the transcription factor Prdm1, which is essential for the specification of the primary slow twitch muscle fibres that derive from adaxial cells. Here we show that Prdm1 executes this function by acting as a transcriptional repressor. Expression of the slow twitch isoform of the myosin heavy chain in adaxial cells is achieved by Prdm1 mediated repression of the transcriptional repressor Sox6. Using Chromatin immuno precipitation (ChIP) we found that genes encoding fast specific isoforms of sarcomeric proteins are direct targets of Prdm1. These genes are ectopically expressed in the adaxial cells of ubotp39 mutant embryos, suggesting that Prdm1 promotes slow twitch fibre differentiation by acting both as a global repressor of fast fibre specific genes as well as of a repressor of slow specific genes. Keywords: ChIP-chip
2008-07-03 | GSE10883 | GEO
Project description:The zebrafish u-boot (ubo) gene encodes the transcription factor Prdm1, which is essential for the specification of the primary slow twitch muscle fibres that derive from adaxial cells. Here we show that Prdm1 executes this function by acting as a transcriptional repressor. Expression of the slow twitch isoform of the myosin heavy chain in adaxial cells is achieved by Prdm1 mediated repression of the transcriptional repressor Sox6. Using Chromatin immuno precipitation (ChIP) we found that genes encoding fast specific isoforms of sarcomeric proteins are direct targets of Prdm1. These genes are ectopically expressed in the adaxial cells of ubotp39 mutant embryos, suggesting that Prdm1 promotes slow twitch fibre differentiation by acting both as a global repressor of fast fibre specific genes as well as of a repressor of slow specific genes. Keywords: ChIP-chip Genomic array design. Microarrays were designed as described below and manufactured by Agilent Technologies (www.agilent.com). We have previously described the ChIP-chip technique in zebrafish and the design of promoter microarrays which cover a 2kb region around the transcription start sites (TSSs) of 11,512 zebrafish genes based on Zv4 (Wardle et al, 2006. Genome Biology 7:R71). In order to capture additional regulatory information further from the basal promoter region we also designed an expanded set of 60mer probes that cover 9kb upstream and 3kb downstream of the TSS of these genes using the same parameters as for the 2kb microarrays. These probe sequences were re-mapped to Zv6 over the course of the project and the coordinates given are for Zv6. We also incorporated several sets of control probes, both positive and negative. On each array there are 769 negative probes designed against zebrafish gene desert regions and Arabidopsis thaliana genes. In addition we included duplicates of promoter probes for several genes that we anticipated may be bound by factors of interest for this and other studies (tnnt3a, mylz2, myhz2, wnt11, flh, vent, msgn1, myod, fgf8, pcdh8) and these probes are arrayed on both slides slide. Finally on each array there are 1804 controls added by Agilent. The final design contained 352,490 probes divided between two microarray slides. Further information on design and manufacture of the microarrays can be found at the Agilent Technologies website.
2010-05-25 | E-GEOD-10883 | biostudies-arrayexpress
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