The overall goal of this proposal is to define the mechanisms that underlie the formation of endocrine cells in the pancreas and to apply this knowledge to instruct human embryonic stem cells (hESCs) to produce functional insulin-secreting beta cells. During the past funding period, work under this grant has determined that ductal progenitors in the pancreas are the major source of endocrine cells during embryonic development. Mechanistic studies in the PI's laboratory have further shown that the transcription factor Sox9 is necessary to bestow competence upon ductal progenitors to initiate endocrine gene expression programs. Moreover, we have demonstrated that Sox9 expression is under control of the Fgf and Notch signaling pathways, suggesting that progenitors need to be exposed to Fgf and Notch signals for endocrine cell differentiation to be initiated. In preliminary studies presented to support a continuation of these studies, we show that Fgf and Notch signaling are aberrantly regulated in current differentiation protocols of hESCs towards pancreatic endocrine beta cells. We hypothesize that the aberrant Fgf and Notch signaling environment accounts for the malfunction of beta- like cells produced in vitro. In this continuing renewal application, the PI proposes a combination of mouse genetic and hESC-based approaches to (a.) further define the mechanisms by which Fgf and Notch signaling orchestrate endocrine cell development and (b.) apply this knowledge to generate functional endocrine cells from hESCs in vitro. To better understand the specific signaling environment necessary for endocrine cell differentiation, Aim 1 will investigate how the Fgf and Notch signaling pathways coordinately control the specification and differentiation of endocrine cells. To aid these experiments, the PI's laboratory has developed unique genetic mouse models.
In Aim 2, we will employ a novel live imaging technology established in the PI's laboratory to monitor the initiation of endocrine cell differentiation at single cell resolution in real time. Based on evidence in othe tissues and organs, experiments under this aim will explore a possible connection between cell division, Notch activity, and the initiation of cell differentiation.
In Aim 3, we will apply paradgms learned from our mouse genetic experiments to direct hESCs towards the beta cell lineage. Experiments under this Aim will directly test how changes in Fgf and Notch signaling affect the maturity of endocrine cells produced from hESCs in vitro. Preliminary evidence from the PI's laboratory suggests that endocrine cell maturity can be improved by providing a Fgf and Notch signaling environment that more closely resembles the environment during normal development. Together, these experiments will aid the identification of culture conditions that support the differentiation of functional beta cells from hESCs in vitro.
Loss of pancreatic insulin-producing beta cells is the hallmark of type 1 diabetes and advanced cases of type 2 diabetes. Studies supported by this grant have led to the discovery of fundamental mechanisms by which beta cells are generated during development and adulthood. The proposed work leverages key findings made during the previous funding period to appropriately instruct human embryonic stem cells (hESCs) to produce functional beta cells in culture.
|Kopp, Janel L; Dubois, Claire L; Schaeffer, David F et al. (2018) Loss of Pten and Activation of Kras Synergistically Induce Formation of Intraductal Papillary Mucinous Neoplasia From Pancreatic Ductal Cells in Mice. Gastroenterology 154:1509-1523.e5|
|Wortham, Matthew; Benthuysen, Jacqueline R; Wallace, Martina et al. (2018) Integrated In Vivo Quantitative Proteomics and Nutrient Tracing Reveals Age-Related Metabolic Rewiring of Pancreatic ? Cell Function. Cell Rep 25:2904-2918.e8|
|Serrill, Jeffrey D; Sander, Maike; Shih, Hung Ping (2018) Pancreatic Exocrine Tissue Architecture and Integrity are Maintained by E-cadherin During Postnatal Development. Sci Rep 8:13451|
|Zeng, Chun; Mulas, Francesca; Sui, Yinghui et al. (2017) Pseudotemporal Ordering of Single Cells Reveals Metabolic Control of Postnatal ? Cell Proliferation. Cell Metab 25:1160-1175.e11|
|Shih, Hung Ping; Panlasigui, Devin; Cirulli, Vincenzo et al. (2016) ECM Signaling Regulates Collective Cellular Dynamics to Control Pancreas Branching Morphogenesis. Cell Rep 14:169-79|
|Barrionuevo, Francisco J; Hurtado, Alicia; Kim, Gwang-Jin et al. (2016) Sox9 and Sox8 protect the adult testis from male-to-female genetic reprogramming and complete degeneration. Elife 5:|
|Wortham, M; Sander, M (2016) Mechanisms of ?-cell functional adaptation to changes in workload. Diabetes Obes Metab 18 Suppl 1:78-86|
|Fox, Raymond G; Lytle, Nikki K; Jaquish, Dawn V et al. (2016) Image-based detection and targeting of therapy resistance in pancreatic adenocarcinoma. Nature 534:407-411|
|Kopp, Janel L; Grompe, Markus; Sander, Maike (2016) Stem cells versus plasticity in liver and pancreas regeneration. Nat Cell Biol 18:238-45|
|Shih, Hung Ping; Seymour, Philip A; Patel, Nisha A et al. (2015) A Gene Regulatory Network Cooperatively Controlled by Pdx1 and Sox9 Governs Lineage Allocation of Foregut Progenitor Cells. Cell Rep 13:326-36|
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