RESUMEN
Identifying the properties of the rapid eye movement (REM) sleep circuitry and its relation to diseases has been challenging due to the neuronal heterogeneity of the brainstem. Here, we show in mice that neurons in the pontine sublaterodorsal tegmentum (SubLDT) that express corticotropin-releasing hormone-binding protein (Crhbp+ neurons) and project to the medulla promote REM sleep. Within the medullary area receiving projections from Crhbp+ neurons, neurons expressing nitric oxide synthase 1 (Nos1+ neurons) project to the SubLDT and promote REM sleep, suggesting a positively interacting loop between the pons and the medulla operating as a core REM sleep circuit. Nos1+ neurons also project to areas that control wide forebrain activity. Ablating Crhbp+ neurons reduces sleep and impairs REM sleep atonia. In Parkinson's disease patients with REM sleep behavior disorders, CRHBP-immunoreactive neurons are largely reduced and contain pathologic α-synuclein, providing insight into the mechanisms underlying the sleep deficits characterizing this disease.
RESUMEN
Considering the fundamental mechanism causing singularity phenomena, we performed the following abduction: Assuming that a multicellular system is driven by spontaneous fluctuation of each cell and dynamic interaction of the cells, state transition of the system would be experimentally predictable from cellular heterogeneity. This study evaluates the abductive hypothesis by analyzing cellular heterogeneity to distinguish pre-state of state transition of differentiating cells with Raman spectroscopy and human induced pluripotent stem cells (hiPSCs) technique. Herein, we investigated the time development of cellular heterogeneity in Raman spectra during cardiomyogenesis of six hiPSC lines and tested two types of analyses for heterogeneity. As expected, some spectral peaks, possibly attributed to glycogen, correctively exhibited higher heterogeneity, prior to intensity changes of the spectrum in the both analyses in the all cell-lines tested. The combination of spectral data and heterogeneity-based analysis will be an approach to the arrival of biology that uses not only signal intensity but also heterogeneity as a biological index.
RESUMEN
Epiblast stem cells (EpiSCs) are pluripotent stem cells derived from epiblasts of postimplantation mouse embryos, and thus provide a useful model for studying "primed" pluripotent states. Here, we devised a simple and robust technique to derive high-quality EpiSCs using an inhibitor of WNT secretion. Using this method, we readily established EpiSC lines with high efficiency and were able to use whole embryonic portions without having to separate the epiblast from the visceral endoderm (VE). Expression analyses revealed that these EpiSCs maintained a homogeneous, undifferentiated status, yet showed high potential for differentiation both in vitro and in teratomas. Unlike EpiSCs derived by the original protocol, new EpiSC lines required continuous treatment with the Wnt inhibitor, suggesting some intrinsic differences from the existing EpiSCs. The homogeneous properties of this new version of EpiSCs should facilitate studies on the establishment and maintenance of a "primed" pluripotent state, and directed differentiation from the primed state.