Project description:In this experiment, we sought to identify how topological organization changes at HoxA cluster in WT, MAZ HoxA(Δ5|6) and CTCF (Δ5|6:6|7) cells during differentiation of mouse embryonic stem cells (ESCs) into cervical motor neurons (MNs).
Project description:In this experiment, we sought to analyze the genes positively or negatively selected during differentiation of mouse embryonic stem cells (ESCs) into cervical motor neurons (MNs) with particular focus on the genes enriched for CTCF boundary disruption at HoxA cluster
Project description:In this experiment, we sought to analyze the genes positively or negatively selected during differentiation of mouse embryonic stem cells (ESCs) into cervical motor neurons (MNs) with particular focus on the genes enriched for CTCF boundary disruption at HoxA cluster
Project description:To identify molecular differences between closely related motor neurons relevant for understanding of neurodegenerative diseases, such as Amyotrophic Lateral Sclerosis (ALS), we exploited induced cranial and spinal motor neuron populations from mouse embryonic stem cells. We performed a large scale time-dependent TMT-based proteomics analysis in the presence and absence of protein misfolding stress. We profiled ~8,600 proteins from two different motor neuron cell lines, measured in two replicates and three time points.
Project description:Proper Homeobox A (HoxA) cluster genes expression is essential for embryonic stem cells (ESCs) differentiation and individual development. However, the mechanisms controlling the precise spatiotemporal expression of HoxA cluster genes during early ESCs differentiation remain largely unknown. Here, we find a CTCF binding element (CBE+47kb) closest to the 3'-end of HoxA locus within a topologically associated domains (TAD) in ESCs. CRISPR-Cas9 mediated the CBE+47kb knockout significantly promotes expression of HoxA cluster genes and early ESCs differentiation induced by RA compared with wild type cells. In mechanism, we found that there was a significant differently long-range chromatin interactions between its adjacent enhancers and HoxA in CBE+47kb knockout cells through chromosome conformation capture assay (Capture-C), indicating that CBE+47kb can precisely organize interactions between its adjacent enhancers and HoxA chromatins. Furthermore, we also showed that its adjacent enhancers deletion shows significantly synthetic inhibition effect on HoxA genes expression, suggesting that these enhancers are required for RA-induced HoxA genes expression. Our study reveals that a new functional CBE+47 can regulate HoxA genes expression through orchestrating long-range chromatin interactions between its adjacent enhancers and HoxA, thus maintaining RA-induced early ESCs proper differentiation.
Project description:Long noncoding RNAs (lncRNAs) have been implicated in controlling various aspects of embryonic stem cell (ESC) biology, although the functions of specific lncRNAs, and the molecular mechanisms through which they act, remain unclear. Here, we demonstrate discrete and opposing roles for the lncRNA transcript Haunt and its genomic locus in regulating the HOXA gene cluster during ESC differentiation. Reducing or enhancing Haunt expression, with minimal disruption of the Haunt locus, led to up- or down-regulation of HOXA genes, respectively. In contrast, increasingly large genomic deletions within the Haunt locus attenuated HOXA activation. The Haunt DNA locus contains potential enhancers of HOXA activation, whereas Haunt RNA acts to prevent aberrant HOXA expression. This work reveals a multi-faceted model of lncRNA-mediated transcriptional regulation of the HOXA cluster, with distinct roles for a lncRNA transcript and its genomic locus, while illustrating the power of rapid CRISPR/Cas9-based genome editing for assigning lncRNA functions. All RNA-seq(s) were designed to reveal the differentially expressed genes among different stages of ESCs differentiation, or differentially expressed genes between wild-type or Haunt or HOXA mutant cells during RA-induced differentiation. All ChIRP-Seq were used to reveal the DNA or RNA targets of Haunt before or after RA treatment.
Project description:In this experiment, we sought to analyze how transcriptome of WT and Maz HoxA(Δ5|6) cells change during differentiation of mouse embryonic stem cells (ESCs) into cervical motor neurons (MNs)
Project description:Amyotrophic Lateral Sclerosis (ALS) results from the selective and progressive degeneration of motor neurons. Although the underlying disease mechanisms remain unknown, glial cells have been implicated in ALS disease progression. Here we examine the effects of glial cell/motor neuron interactions on gene expression, using the hSOD1G93A mouse model of ALS. We detect striking cell autonomous and non-autonomous changes in gene expression in co-cultured motor neurons and glia, revealing that the two cell types profoundly affect each other. In addition, we found a remarkable concordance between the cell culture data, expression profiles of whole spinal cords, and of acutely isolated spinal cord cells, during disease progression in the G93A mouse model, providing validation of the cell culture approach. Bioinformatics analyses identified changes in the expression of specific genes and signaling pathways that may contribute to motor neuron degeneration in ALS, among which are TGF-b signaling pathways. RNA-seq profiles of: 1) 43 Sandwich culture samples at 3 different time points (3, 7 and 14 days), in duplicate, in different combinations of genetic background WT/SOD1_G93A mutant glia and WT/SOD1_G93A mutant neurons; 2) 16 spinal cord samples at 4 different time points, WT and SOD1_G93A mutant.
Project description:The motor neuron (MN)–hexamer complex consisting of LIM homeobox 3, Islet-1, and nuclear LIM interactor is a key determinant of motor neuron specification and differentiation. To gain insights into the transcriptional network in motor neuron development, we performed a genome-wide ChIP-sequencing analysis and found that the MN–hexamer directly regulates a wide array of motor neuron genes by binding to the HxRE (hexamer response element) shared among the target genes. Interestingly, STAT3-binding motif is highly enriched in the MN–hexamer–bound peaks in addition to the HxRE. We also found that a transcriptionally active form of STAT3 is expressed in embryonic motor neurons and that STAT3 associates with the MN–hexamer, enhancing the transcriptional activity of the MN–hexamer in an upstream signal-dependent manner. Correspondingly, STAT3 was needed for motor neuron differentiation in the developing spinal cord. Together, our studies uncover crucial gene regulatory mechanisms that couple MN–hexamer and STAT-activating extracellular signals to promote motor neuron differentiation in vertebrate spinal cord. To explain our experimental scheme briefly, we are interested in finding target sites for the dimer of transcription factors Isl1 and Lhx3. To mimic the biological activity of Isl1/Lhx3 dimer, we made Isl1-Lhx3 fusion and found that Isl1-Lhx3 has a potent biological activity in multiple systems (i.e. generation of ectopic motor neurons). Then we made ES cell line that induces Flag-tagged Isl1-Lhx3 expression upon Dox treatment. These *mouse* ES cells differentiate to motor neurons (iMN-ESCs) when treated with Dox following EB formation. To identify genomic binding sites of Isl1-Lhx3 (Flag-tagged), we performed ChIP with Flag antibody (pull down of Flag-Isl1-Lhx3) in ES cells treated with Dox. ChIP with Flag antibody in ES cells treated with vehicle (no Dox) was done as a negative control in parallel, and sequenced along with +Dox sample. We have done these experiments twice (two sets).