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bioRxiv · 10.1101/538801

C. elegans synMuv B proteins regulate spatial and temporal chromatin compaction during development

Costello, M. E.·Petrella, L.
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Abstract

Tissue-specific establishment of repressive chromatin through creation of compact chromatin domains during development is necessary to ensure proper gene expression and cell fate. C. elegans synMuv B proteins are important for the soma/germline fate decision and mutants demonstrate ectopic germline gene expression in somatic tissue, especially at high temperature. We show that C. elegans synMuv B proteins regulate developmental chromatin compaction and that timing of chromatin compaction is temperature sensitive in both wild-type and synMuv B mutants. Chromatin compaction in mutants is delayed into developmental time-periods when zygotic gene expression is upregulated and demonstrates an anterior-to-posterior pattern. Loss of this patterned compaction coincides with the developmental time-period of ectopic germline gene expression that leads to a developmental arrest in synMuv B mutants. Thus, chromatin organization throughout development is regulated both spatially and temporally by synMuv B proteins to establish repressive chromatin in a tissue-specific manner to ensure proper gene expression.

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Costello, M. E., Petrella, L.. 2019-02-02. C. elegans synMuv B proteins regulate spatial and temporal chromatin compaction during development. https://doi.org/10.1101/538801

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