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Allogeneic islet transplantation is limited by adverse effects of chronic immunosuppression used to control rejection. The programmed cell death 1 pathway as an important immune checkpoint has the potential to obviate the need for chronic immunosuppression. We generated an oligomeric form of programmed cell death 1 ligand chimeric with core streptavidin (SA-PDL1) that inhibited the T effector cell response to alloantigens and converted T conventional cells into CD4+Foxp3+ T regulatory cells. The SA-PDL1 protein was effectively displayed on the surface of biotinylated mouse islets without a negative impact islet viability and insulin secretion. Transplantation of SA-PDL1-engineered islet grafts with a short course of rapamycin regimen resulted in sustained graft survival and function in >90% of allogeneic recipients over a 100-d observation period. Long-term survival was associated with increased levels of intragraft transcripts for innate and adaptive immune regulatory factors, including IDO-1, arginase-1, Foxp3, TGF-β, IL-10, and decreased levels of proinflammatory T-bet, IL-1β, TNF-α, and IFN-γ as assessed on day 3 posttransplantation. T cells of long-term graft recipients generated a proliferative response to donor Ags at a similar magnitude to T cells of naive animals, suggestive of the localized nature of tolerance. Immunohistochemical analyses showed intense peri-islet infiltration of T regulatory cells in long-term grafts and systemic depletion of this cell population resulted in prompt rejection. The transient display of SA-PDL1 protein on the surface of islets serves as a practical means of localized immunomodulation that accomplishes sustained graft survival in the absence of chronic immunosuppression with potential clinical implications. Copyright © 2020 by The American Association of Immunologists, Inc.Despite clear physiological roles, the ventromedial hypothalamus (VMH) developmental programs are poorly understood. Here, we asked whether the proneural gene, Achaete-scute homolog1 (Ascl1), contributes to VMH development. Ascl1 transcripts were detected in E10.5-P0 VMH neural progenitors. The elimination of Ascl1 reduced the number of VMH neurons at E12.5 and E15.5, particularly within the VMH-central (VMHC) and -dorsomedial (VMHDM) subdomains and resulted in a VMH cell fate change from glutamatergic to GABAergic. We observed a loss of Neurog3 expression in Ascl1 -/- hypothalamic progenitors and an upregulation of Neurog3 when Ascl1 was overexpressed. We also demonstrated a glutamatergic to GABAergic fate switch in Neurog3-null mutant mice, suggesting that Ascl1 might act via Neurog3 to drive VMH cell fate decisions. We also showed a concomitant increase in the central GABAergic fate determinant Dlx1/2 expression in the Ascl1-null hypothalamus. However, Ascl1 was not sufficient to induce an ectopic VMH fate when overexpressed outside of the normal window of competency. Combined, Ascl1 is required but not sufficient to specify the neurotransmitter identity of VMH neurons, acting in a transcriptional cascade with Neurog3. © 2020. Published by The Company of Biologists Ltd.The transcription factor Zeb2 controls fate specification and subsequent differentiation and maturation of multiple cell types in various embryonic tissues. It binds many protein partners, including activated Smad proteins and the NuRD co-repressor complex. How Zeb2 subdomains support cell differentiation in various contexts has remained elusive. Here, we have studied the role of Zeb2 and its domains in neurogenesis and neural differentiation in the young postnatal ventricular-subventricular zone (V-SVZ), where neural stem cells generate olfactory bulb-destined interneurons. Conditional Zeb2 knockouts and separate acute loss- and gain-of-function approaches indicated that Zeb2 is essential to control apoptosis and neuronal differentiation of V-SVZ progenitors before and after birth, and identified Sox6 as Zeb2-dependent and potential downstream target gene. Zeb2 genetic inactivation impaired the differentiation potential of the V-SVZ niche in a cell-autonomous fashion. We also provide evidence that its normal function in the V-SVZ involves non-autonomous mechanisms as well. Additionally, we could demonstrate distinct roles for Zeb2 protein-binding domains, suggesting that Zeb2 partners co-determine neuronal output from the mouse V-SVZ in both quantitative and qualitative manners in early postnatal life. © 2020. Published by The Company of Biologists Ltd.Cleft lip is one of the most common human birth defects. However, there remain a limited number of mouse models of cleft lip that can be leveraged to characterize genes and mechanisms that cause this disorder. While crosstalk between epithelial and mesenchymal cells underlies formation of the face and palate, the basic molecular events mediating this crosstalk remain poorly understood. We previously demonstrated that mice lacking epithelial-specific splicing factor Esrp1 have fully penetrant bilateral CL/P. selleck kinase inhibitor In this study we further investigated the mechanisms leading to cleft lip as well as cleft palate in both existing and new Esrp1 mutant mouse models. These studies included a detailed transcriptomic analysis of changes in ectoderm and mesenchyme in Esrp1 -/- embryos during face formation. We identified altered expression of genes previously implicated in cleft lip and/or palate, including components of multiple signaling pathways. These findings provide the foundation for detailed investigations using Esrp1 mutant disease models to examine gene regulatory networks and pathways that are essential for normal face and palate development and whose disruption leads to orofacial clefting in human patients. © 2020. Published by The Company of Biologists Ltd.Much of our current knowledge of biological chemistry is founded in the structure-function relationship, whereby sequence determines structure that determines function. Thus, the discovery that a large fraction of the proteome is intrinsically disordered, while being functional, has revolutionized our understanding of proteins and raised new and interesting questions. Many intrinsically disordered proteins (IDPs) have been determined to undergo a disorder to order transition when recognizing their physiological partners, suggesting their mechanisms of folding are intrinsically different from those observed in globular proteins. However, IDPs also follow some of the classic paradigms established for globular proteins, pointing to important similarities in their behavior. In this review, we compare and contrast the folding mechanisms of globular proteins with the emerging features of binding-induced folding of intrinsically disordered proteins. Specifically, whilst disorder-to-order transitions of intrinsically disordered proteins appear to follow rules of globular protein folding such as the cooperative nature of the reaction, their folding pathways are remarkably more malleable, due to the heterogeneous nature of their folding nuclei, as probed by analysis of linear free energy relationship plots.