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Balwierz, P.

Publications and source records attributed to Balwierz, P..

2 recordsLinked to original sources

Integrative annotation of genomic features reveal functional elements and epigenetic landscapes in the developing zebrafish

Zebrafish, a popular model for embryonic development and for modelling human diseases, has so far lacked a systematic functional annotation programme akin to those in other animal models. To address this, we formed the international DANIO-CODE consortium and created the first central repository to store and process zebrafish developmental functional genomic data. Our Data Coordination Center (https://danio-code.zfin.org) combines a total of 1,802 sets of unpublished and reanalysed published genomics data, which we used to improve existing annotations and show its utility in experimental design. We identified over 140,000 cis-regulatory elements in development, including novel classes with distinct features dependent on their activity in time and space. We delineated the distinction between regulatory elements active during zygotic genome activation and those active during organogenesis, identifying new aspects of how they relate to each other. Finally, we matched regulatory elements and epigenomic landscapes between zebrafish and mouse and predict functional relationships between them beyond sequence similarity, extending the utility of zebrafish developmental genomics to mammals.

developmental biology↗

Germ plasm localisation dynamics mark distinct phases of transcriptional and post-transcriptional regulation control in primordial germ cells

In many animal models, primordial germ cell (PGC) development depends on maternally-deposited germ plasm to avoid somatic cell fate. Here, we show that PGCs respond to regulatory information from the germ plasm in two distinct phases and mechanisms in zebrafish. We show that PGCs commence zygotic genome activation together with the rest of the embryo with no demonstrable differences in transcriptional and chromatin accessibility levels. Thus, cytoplasmic germ plasm determinants only affect post-transcriptional stabilisation of RNAs to diverge transcriptome from somatic cells, which, unexpectedly, also activate germ cell-specific genes. Perinuclear relocalisation of germ plasm is coupled to dramatic divergence in chromatin opening and transcriptome from somatic cells characterised by PGC-specific chromatin topology. Furthermore, we reveal Tdrd7, regulator of germ plasm localisation, as crucial determinant of germ fate acquisition.

developmental biology↗