Project description:In the developing mouse brain, PRDM16 exhibits robust expression in radial glia (RG) progenitors, serving as one of the conserved core RG genes shared between humans and mice. Much is known regarding the functions of PRDM16 in the developing mouse brain, yet its roles in the developing human brain are less explored. Our study was motivated by detecting a patient with a de novo nonsense mutation in PRDM16 exhibiting lissencephaly and microcephaly features. We introduced the mutation in human stem cells in both homozygous and heterozygous manner and generated human cortical organoids. The organoids differed in cell cycle parameters, and RNA-seq demonstrated changes in cell adhesion and WNT-signaling, which were confirmed by immunostaining. We further generated ChIP-seq data from human fetuses and compared the results to ChIP-seq data previously obtained from mice and differentially expressed genes in humans and mice (REFS he and baizabal papers). The top detected motif matched LHX2, so we compared our data with recently acquired LHX2 ChIP-seq data from the mouse. Our studies show highly conserved genes and pathways suggesting that PRDM16 and LHX2 complex and collaborate in the developing mouse and human brains. The multifaceted nature of PRDM16 and its intricate involvement in transcriptional regulation and various developmental processes highlight its importance in understanding neurodevelopmental mechanisms.
Project description:PRDM16 is a dynamic transcriptional regulator of various stem cell niches, including adipocytic, hematopoietic, cardiac progenitors, and neural stem cells. PRDM16 has been suggested to contribute to 1p36 deletion syndrome, one of the most prevalent subtelomeric microdeletion syndromes. We report a patient with a de novo nonsense mutation in the PRDM16 coding sequence, accompanied by lissencephaly and microcephaly features. Human stem cells were genetically modified to mimic this mutation, generating cortical organoids that exhibited altered cell cycle dynamics. RNA sequencing of cortical organoids at day 32 unveiled changes in cell adhesion and WNT-signaling pathways. ChIP-seq of PRDM16 identified binding sites in postmortem human fetal cortex, indicating the conservation of PRDM16 binding to developmental genes in mice and humans, potentially at enhancer sites. A shared motif between PRDM16 and LHX2 was identified and further examined through comparison with LHX2 ChIP-seq data from mice. These results suggested a collaborative partnership between PRDM16 and LHX2 in regulating a common set of genes and pathways in cortical radial glia cells, possibly via their synergistic involvement in cortical development.
Project description:Here, we identified Prdm16 as a FAPs-enriched factor that mediates their developmental capacities by modulating H3K9me2-marked heterochromatin organization at the nuclear lamina. We show that deletion of Prdm16 prevents FAPs adipogenic differentiation and unlocks a myogenic capacity. We found that Prdm16 localizes at the nuclear lamina where it cooperates with the H3K9 methyltransferases (KMTs), G9a and GLP, to mediate H3K9me2 deposition.
Project description:Purpose:To gain a deeper insight into how PRDM16 regulates neuron-vascular communication for angiogenesis, RNA-sequencing (RNA-seq) was performed to analyze the genome-wide changes by PRDM16 deletion at E15. Methods: Total RNA was extracted from E15 telencephalic tissue of Prdm16cKO and Prdm16fl/fl mice. Then total RNA was quality controlled and quantified using an Agilent 2100 Bioanalyzer. After converting to cDNA and building library, high-throughput sequencing was performed using the Illumina HiSeq 2500 platform in Annoroad Genomics. Results: Approximately approximately one thousand transcripts showed differential expression between the Prdm16fl/fl and Prdm16cKO brain cortex, with a fold change ≥1.5 and p value <0.05. Gene ontology (GO) analysis showed that the down-regulated genes were enriched in the terms related to neurogenesis, blood vessel development and secretion by cells. Up-regulated genes showed a significant enrichment of terms involved in negative regulation of cell communication and negative regulation of angiogenesis. These results reflected the importance of PRDM16 in cortical development. Conclusions: We conclude that RNA-seq based transcriptome characterization would provide a framework for understanding how Prdm16 gene contribute to brain cortical development.
Project description:Gene expression profile from brown adipose tissues of Prdm16 knockout and wile type mice. Prdm16 is a transcription factor that regulates the thermogenic gene program in brown and beige adipocytes. However, whether Prdm16 is required for the development or physiological function of brown adipose tissue (BAT) in vivo has been unclear. By analyzing mice that selectively lacked Prdm16 in the brown adipose lineage, we found that Prdm16 was dispensable for embryonic BAT development. Brown adipose tissues were collected from Prdm16 knockout and wiletype mice with 4 biological replicates per condition. Experiment was done in two separate batch for 6-week-old and 11-month-old. Extracted RNA was hybridized to Agilent two-color arrays.
Project description:Expression of the lim-homeodomain transcription factor is required for sustained maintenance of heamatopoietic stem cell like cells in undifferentiated form durng in vitro culturing. Cell lines were created from the mouse embryonic stem (ES) cell line, Ainv15. The gene Lhx2 was introducted into these cells under the control of a tetracycline-responsive element. In the presence of tetracycline (or its analogue doxycycline), these cells express Lhx2. In DoxHPC7 GFP is co-expressed together with the Lhx2 gene. We used these cells to carry out a time-course study where the effects of Lhx2 withdrawal were studied.
Project description:The Lhx2 transcription factor plays essential roles in morphogenesis and patterning of ectodermal derivatives, as well as in controlling stem cell activity. Lhx2 is expressed in the hair follicle (HF) buds, while in postnatal telogen HFs Lhx2+ cells reside in the stem cell-enriched epithelial compartments (bulge, secondary hair germ) and co-express selected stem cell markers (Sox9, Tcf4 and Lgr5). Lhx2+ cells represent the vast majority of cells in the bulge and secondary hair germ that proliferate in response to skin injury. This is functionally important, since the wound re-epithelialization is significantly retarded in heterozygous Lhx2 knockout (+/-) mice, while anagen onset in the HFs located closely to the wound is accelerated compared to wild-type mice. Cell proliferation in the bulge and the number of Sox9+ and Tcf4+ cells in the HFs closely adjacent to the wound in Lhx2+/- mice are decreased in comparison to wild-type controls, while expression of Lgr5 and cell proliferation in the secondary hair germ are increased. Furthermore, acceleration of wound-induced anagen development in Lhx2+/- mice is inhibited by administration of Lgr5 siRNA. In addition, Chip-on-chip/ChIP-qPCR and reporter assay analyses reveal Sox9, Tcf4 and Lgr5 as direct Lhx2 targets in keratinocytes. These data strongly suggest that Lhx2 positively regulates Sox9 and Tcf4 in the bulge cells and promotes wound re-epithelization, while it simultaneously negatively regulates Lgr5 in the secondary hair germ and inhibits HF cycling. Thus, Lhx2 operates as a regulator of epithelial stem cell activity during skin response to injury. Chromatin form primary mouse keratinocytes (PMK) was subjected to ChIP analysis with Lhx2 antibody; input and ChIP DNA were labelled with Cy3 and Cy5 respectivly and used form Nimblegen MM8 Mouse Promoter Array
Project description:Lhx2 is a LIM-homeobox transcription factor which could induce hematopoietic stem cell-like cells from mouse embryonic stem cells and induced pluripotent stem cells. However, the effects of Lhx2 overexpression in the human chronic myeloid leukemia cell line K562 remains unknown. Therefore we carried out Lhx2 overexpression in K562 cells.
Project description:Mutation of the PRDM16 gene causes human dilated and noncompaction cardiomyopathy. The PRDM16 protein is a transcriptional regulator that affects cardiac development via Tbx5 and Hand1, thus regulating myocardial structure. The biallelic inactivation of Prdm16 induces severe cardiac dysfunction with postnatal lethality and hypertrophy in mice. The early pathological events that occur upon Prdm16 inactivation have not been explored. This study performed in-depth pathophysiological and molecular analyses of male and female Prdm16csp1/wt mice that carry systemic, monoallelic Prdm16 gene inactivation. We systematically assessed early molecular changes through transcriptomics, proteomics, and metabolomics. Kinetic modelling of cardiac metabolism was performed in silico with CARDIOKIN.
Project description:The Lhx2 transcription factor plays essential roles in morphogenesis and patterning of ectodermal derivatives, as well as in controlling stem cell activity. Lhx2 is expressed in the hair follicle (HF) buds, while in postnatal telogen HFs Lhx2+ cells reside in the stem cell-enriched epithelial compartments (bulge, secondary hair germ) and co-express selected stem cell markers (Sox9, Tcf4 and Lgr5). Lhx2+ cells represent the vast majority of cells in the bulge and secondary hair germ that proliferate in response to skin injury. This is functionally important, since the wound re-epithelialization is significantly retarded in heterozygous Lhx2 knockout (+/-) mice, while anagen onset in the HFs located closely to the wound is accelerated compared to wild-type mice. Cell proliferation in the bulge and the number of Sox9+ and Tcf4+ cells in the HFs closely adjacent to the wound in Lhx2+/- mice are decreased in comparison to wild-type controls, while expression of Lgr5 and cell proliferation in the secondary hair germ are increased. Furthermore, acceleration of wound-induced anagen development in Lhx2+/- mice is inhibited by administration of Lgr5 siRNA. In addition, Chip-on-chip/ChIP-qPCR and reporter assay analyses reveal Sox9, Tcf4 and Lgr5 as direct Lhx2 targets in keratinocytes. These data strongly suggest that Lhx2 positively regulates Sox9 and Tcf4 in the bulge cells and promotes wound re-epithelization, while it simultaneously negatively regulates Lgr5 in the secondary hair germ and inhibits HF cycling. Thus, Lhx2 operates as a regulator of epithelial stem cell activity during skin response to injury.