Project description:Single-cell RNA sequencing was performed on embryonic Drosophila heart cells. Analysis of single-cell RNA sequence (scRNA-seq) data at timepoints prior to migration of cardiac progenitor cells through to heart tube closure (embryonic stages 13, 14-early, 14-late, 15 and 16) revealed several interesting findings. We found specification of cardiac cell types takes place early, before stage 13, with biggest changes in transcriptomic profiles detected once cells had settled at the midline for further cardioblast maturation. Throughout development, our data identified multiple cell types, covering cardioblasts and five types of pericardial cells including a neural cardiac cell type. The scRNA-seq data further revealed a combination of first and second heart fields during heart development in fly. Further, we uncovered new cell type-specific markers discerning the different cardiac cell types. And we identified signaling pathways key to heart cell maturation, which are conserved from fly to human.
Project description:Development of specialized cell types and structures in the vertebrate heart is regulated by spatially-restricted molecular pathways. Disruptions in these pathways can cause severe congenital cardiac malformations or functional defects. To better understand these pathways and how they regulate cardiac development and function we used tomo-seq, combining high-throughput RNA sequencing with tissue sectioning, to establish a genome-wide expression dataset with high spatial resolution for the developing zebrafish heart. Analysis of the dataset revealed over 1100 genes differentially expressed in sub-compartments. Pacemaker cells in the sinoatrial region induce heart contractions, but little is known about the mechanisms underlying their development and function. Using our transcriptome map, we identified spatially restricted Wnt/β-catenin signaling activity in pacemaker cells, which was controlled by Islet-1 activity. Moreover, Wnt/β-catenin signaling at a specific developmental stage in the myocardium controls heart rate by regulating pacemaker cellular response to parasympathetic stimuli. Thus, this high-resolution transcriptome map incorporating all cell types in the embryonic heart can expose spatially-restricted molecular pathways critical for specific cardiac functions.
Project description:We report bulk RNA-sequencing, ChIP-seq, and ATAC-seq of endothelial cells harvested from heart and lung of multiple mouse strains investigating the role of KLF2 and KLF4 in endothelial transcription
Project description:Heart biopsies of explanted organ after heart failure. Same patient, 3 different sample types. 1,2,6 - from paraffin tissue, Thermo fisher kit 3,4,5 - from paraffin tissue, Qiagen kit 7,8,9 - fresh tissue with Qiagen kit
Project description:The vertebrate heart is the first organ to form in the embryo and is composed of mesodermal progenitors that arise in an area termed the cardiac crescent. These give rise not only to muscle cells but also to a variety of other cell types, all of which work together to allow the heart to beat rhythmically. Current understanding of when and how these different cell types arise during early cardiogenesis is limited. Therefore, we microdissected the cardiac crescent region of mouse embryos at different stages of development -from when the structure is first present until the linear heart tube (LHT) stage- and performed single-cell RNA-sequencing. The present submission contains pilot data from the LHT.
Project description:Heart valve disease affects up to 30% of the population and has been shown to have origins during embryonic development. Valvulogenesis begins with formation of endocardial cushions in the atrioventricular canal and outflow tract regions. Subsequently, endocardial cushions remodel, elongate and progressively form mature valve structures composed of a highly organized connective tissue that provides the necessary biomechanical function throughout life. While endocardial cushion formation has been well studied, the processes required for valve remodeling are less well understood. The transcription factor Scleraxis (Scx) is detected in mouse valves from E15.5 during initial stages of remodeling, and expression remains high until birth when formation of the highly organized mature structure is complete. Heart valves from Scx-/- mice are abnormally thick and develop fibrotic phenotypes similar to human disease by juvenile stages. These phenotypes begin around E15.5 and are associated with defects in connective tissue organization and valve interstitial cell differentiation. In order to understand the etiology of this phenotype, we analyzed the transcriptome of remodeling valves isolated from E15.5 Scx-/- embryos using RNA-seq. From this, we have identified a profile of protein and non-protein mRNAs that are dependent on Scx function and using bioinformatics we can predict the molecular functions and biological processes affected by these genes. These include processes and functions associated with gene regulation (methyltransferase activity, DNA binding, Notch signaling), vitamin A metabolism (retinoic acid biosynthesis) and cellular development (cell morphology, cell assembly and organization). In addition, several mRNAs are affected by alternative splicing events in the absence of Scx, suggesting additional roles in post-transcriptional modification. In summary, our findings have identified transcriptome profiles from abnormal heart valves isolated from E15.5 Scx-/- embryos that could be used in the future to understand mechanisms of heart valve disease in the human population.