Project description:ChIP-seq was used to generate chromatin state maps, profile binding patterns of key architectural proteins and locate putative enhancer regions in the early development (TB stage) and developing gonads of the marine chrodate Oikopleura dioica.
Project description:ATAC-seq was used to locate putative enhancer regions in the early development (tailbud stage), developing male and female gonads of the marine chrodate Oikopleura dioica.
Project description:In multicellular organisms, histone posttranslational modifications plays roles in transitions associated with the cell cycle, development, germline specification, gametogenesis and inheritance. Here we defined adaptations of an epigenome in tunicates, sister group to vertebrates, to strong secondary genome compaction in the larvacean, Oikopleura dioica, that has separate sexes and male heterogamy. We profiled 19 histone post-translational modifications in homogeneous ovary and testis samples and used the combinatorics of these marks to define chromatin states. We supplemented these with profiles of RNA polymerase II, CTCF and p300 binding sites and integrated existing annotation and expression data to characterize distinct epigenomic landscapes of the ovary and testis.
Project description:Polycistronic mRNAs transcribed from operons are resolved via the trans-splicing of a spliced leader (SL) RNA. The SL is also frequently trans-spliced to monocistronic transcripts. Using a modified cap analysis of gene expression (CAGE) protocol we mapped sites of SL trans-splicing genome-wide in the marine chordate Oikopleura dioica and find evidence for proposed functions of SL-trans-splicing. A recent hypothesis postulates that operons facilitate recovery from growth arrested states in metazoans. We examined the expression dynamics of operons across the life-cycle of the animal and during growth arrest recovery. We show that operons do not facilitate recovery from growth arrest in O. dioica. We find that operons are enriched in the germline and that trans-spliced transcripts are predominantly maternal., Interestingly, there is a TOP-like motif in the SL sequence, and trans-splicing in TOP mRNAs, indicating that trans-spliced mRNAs are targets for nutrient-dependent translational control in O. dioica.
