Project description:Co-development of the lungs and heart underlies key evolutionary innovations in the transition to terrestrial life. Cardiac specializations that support pulmonary circulation, including the atrial septum, are generated by second heart field (SHF) cardiopulmonary progenitors (CPPs). It has been presumed that transcription factors required in the SHF for cardiac septation, e.g. Tbx5, directly drive a cardiac morphogenesis gene regulatory network. Here, we report instead that TBX5 directly drove Wnt ligands to initiate a bi-directional signaling loop between cardiopulmonary mesoderm and the foregut endoderm for endodermal pulmonary specification, and subsequently, atrial septation. TBX5 ChIP-seq identified cis-regulatory elements at Wnt2 sufficient for endogenous Wnt2 expression domains in vivo and required for Wnt2 expression in pre-cardiac mesoderm in vitro. Thus, Tbx5 initiated a mesoderm-endoderm-mesoderm signaling loop in lunged vertebrates that provides a molecular basis for the co-evolution of pulmonary and cardiac structures required for terrestrial life.
Project description:The aim of this BBSRC-funded project is to develop laser-capture microdissection (LCMD) to isolate small cell clusters in different regions of arabidopsis embryos at different stages of development; to develop RNA amplification procedures on dissected tissue sampes; and to use DNA microarray techniques to investigate global transcriptional differences between samples. Cryosectioned embryos of ecotype Col-O of globular, heart and torpedo stage were used to isolate cell clusters from the apical and basal regions, for RNA isolation and amplification. !Samples will be provided as T7-primed cDNA, with three biological replicates for each tissue to be analysed. Each replicate comprises cDNA from pooled tissue samples from ca. 15 embryos. The experimental details have been discussed with Sean May et al. at NASC. Experimenter name = Stuart Casson and Matthew Spencer Experimenter phone = 0191 374 7356 Experimenter fax = 0191 374 2417 Experimenter institute = Durham University Experimenter address = Integrative Cell Biology Laboratory Experimenter address = School of Biological Sciences Experimenter address = Durham University Experimenter address = South Road Experimenter address = Durham Experimenter zip/postal_code = DH1 3LE Experimenter country = UK Keywords: organism_part_comparison_design; development_or_differentiation_design
Project description:We report the continuous patterning and dynamic morphogenesis of hepatic, biliary and pancreatic structures, invaginating from a three-dimensional culture of human pluripotent stem cell (PSC). The boundary interactions between anterior and posterior gut spheroids differentiated from human PSCs enables autonomous emergence of hepato-biliary-pancreatic (HBP) organ domains specified at the foregut-midgut boundary organoids in the absence of extrinsic factor supply. The regional identity of the boundary region of anterior-posteior spheroids was analyzed by RNA-sequencing with micro-dissected boundary organoid into anterior, posterior, and boundary regions. Each region expressed the corresponding gut lineage markers. The early HBP specification markers including HHEX1 and PDX1 at the boundary were highly upregulated compared with the other two regions, indicating that the anterior-posterior boundary interactions autonomously generate HHEX and PDX1 positive cells in the absence of exogenous inductive factors. To delineate the HBP progenitor self-inductive mechanism, we evaluated the boundary specific expression profiles of known inductive signaling pathways that includes FGF, BMP, Hedgehog, NOTCH and retinoic acid (RA) signals, and found that the signal downstream of RA were activated prominently at the boundary region but not in the anterior or posterior regions.
Project description:The aim of this BBSRC-funded project is to develop laser-capture microdissection (LCMD) to isolate small cell clusters in different regions of arabidopsis embryos at different stages of development; to develop RNA amplification procedures on dissected tissue sampes; and to use DNA microarray techniques to investigate global transcriptional differences between samples. Cryosectioned embryos of ecotype Col-O of globular, heart and torpedo stage were used to isolate cell clusters from the apical and basal regions, for RNA isolation and amplification. !Samples will be provided as T7-primed cDNA, with three biological replicates for each tissue to be analysed. Each replicate comprises cDNA from pooled tissue samples from ca. 15 embryos. The experimental details have been discussed with Sean May et al. at NASC. Experimenter name = Stuart Casson and Matthew Spencer; Experimenter phone = 0191 374 7356; Experimenter fax = 0191 374 2417; Experimenter institute = Durham University; Experimenter address = Integrative Cell Biology Laboratory; Experimenter address = School of Biological Sciences; Experimenter address = Durham University; Experimenter address = South Road; Experimenter address = Durham; Experimenter zip/postal_code = DH1 3LE; Experimenter country = UK Experiment Overall Design: 27 samples were used in this experiment
Project description:We here systematically studied the interaction network of bone marrow cells. To this end, we micro-dissected many small interacting structures (cell doublets, triplets etc.) into single cells, and sequenced their mRNAs, to infer cell identity. After grouping the cells into cell types (based on the single-cell transcriptomes), we identified actual physical interactions that occurred more, or less, than what would be expected by chance. We compared the micro-dissected data to sorted hematopoietic stem cells.
Project description:We here systematically studied the interaction network of bone marrow cells. To this end, we micro-dissected many small interacting structures (cell doublets, triplets etc.) into single cells, and sequenced their mRNAs, to infer cell identity. After grouping the cells into cell types (based on the single-cell transcriptomes), we identified actual physical interactions that occurred more, or less, than what would be expected by chance. We compared the micro-dissected data to sorted hematopoietic stem cells. After mild dissociation of the bone marrow, we micro-dissected many small interacting structures (cell doublets, triplets etc.) into single cells, and sequenced their mRNAs. In addition, single hematopoietic stem cells were sorted (Lineage- Kit+ Sca1+ CD150+ CD48-) to sequence their transcriptome. In detail, the bone marrow was mildly flushed. Structures composed of about 10 to 20 cells were set apart. With needles and a micro-dissection microscope, we trimmed of smaller structures from these big structure. These smaller structures are mainly two to four cells attached together. These small structures were then further micro-dissected to single cells. The goal of doing these sequential dissections was to keep track of which cells were interacting with which. Each micro-dissected cell sample contains RNA-seq data for 96 single cells. Each single cells received a different barcode that allow us to entangle them, and to produce the processed .coutt.csv file. Each sorted hematopoietic stem cell sample represents a single cell. The processed data file expdata_BMJhscC.csv contains transcript counts for all analyzed cells.
Project description:We here systematically studied the interaction network of bone marrow cells. To this end, we micro-dissected many small interacting structures (cell doublets, triplets etc.) into single cells, and sequenced their mRNAs, to infer cell identity. After grouping the cells into cell types (based on the single-cell transcriptomes), we identified actual physical interactions that occurred more, or less, than what would be expected by chance.
Project description:Spatial transcriptomics and multiplexed imaging are complementary methods for studying tissue biology. Here we describe a simple method for transcriptional profiling of formalin fixed histology specimens based on mechanical isolation of tissue micro-regions containing 5-20 cells. Sequencing micro-regions from an archival melanoma specimen having multiple distinct histologies reveals significant differences in transcriptional programs associated with tumor invasion, proliferation, and immunoediting and parallel imaging confirms changes in immuno-phenotypes and cancer cell states.