Publications by authors named "Samuel Z H Wong"

Cell competition acts as a quality-control mechanism that eliminates cells less fit than their neighbors to optimize organ development. Whether and how competitive interactions occur between neural progenitor cells (NPCs) in the developing brain remains unknown. Here, we show that endogenous cell competition occurs and intrinsically correlates with the Axin2 expression level during normal brain development.

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Article Synopsis
  • The neuroendocrine system includes various types of neurons, with hypothalamic KNDy neurons being crucial for starting puberty.
  • Recent studies identified mutations in the TBX3 gene as linked to delayed puberty, prompting research into how Tbx3 influences the development and function of these KNDy neurons.
  • Findings indicate that Tbx3 plays a critical role in maintaining KNDy neuron identity and that mutations in this gene disrupt normal cellular processes, leading to puberty-related issues.
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Ependymoma (EPN) is a malignant glial tumor occurring throughout central nervous system, which commonly presents in children. Although recent studies have characterized EPN samples at both the bulk and single-cell level, intratumoral heterogeneity across subclones remains a confounding factor that impedes understanding of EPN biology. In this study, we generated a high-resolution single-cell dataset of pediatric ependymoma with a particular focus on the comparison of subclone differences within tumors and showed upregulation of cilium-associated genes in more highly differentiated subclone populations.

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  • Human brain organoids, specifically arcuate organoids (ARCOs), have been created from human induced pluripotent stem cells to study the hypothalamic arcuate nucleus and its development.
  • Single-cell RNA sequencing of these organoids shows significant diversity in cellular makeup and highlights a distinct molecular signature related to the human arcuate nucleus.
  • ARCOs derived from Prader-Willi syndrome patients demonstrate abnormal differentiation and inflammatory responses, making them valuable models for exploring hypothalamic development and related diseases.
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The hypothalamus plays crucial roles in regulating endocrine, autonomic, and behavioral functions via its diverse nuclei and neuronal subtypes. The developmental mechanisms underlying ontogenetic establishment of different hypothalamic nuclei and generation of neuronal diversity remain largely unknown. Here, we show that combinatorial T-box 3 (TBX3), orthopedia homeobox (OTP), and distal-less homeobox (DLX) expression delineates all arcuate nucleus (Arc) neurons and defines four distinct subpopulations, whereas combinatorial NKX2.

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  • * Researchers found that while neurons and astrocytes were only lightly infected, choroid plexus epithelial cells were significantly affected, leading to cell death and signs of inflammation.
  • * The findings support using human induced pluripotent stem cell-derived brain organoids to further explore how SARS-CoV-2 infects brain cells and the resulting dysfunction, potentially aiding in developing treatment strategies.
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  • Neurological complications frequently occur in COVID-19 patients, but the impact of SARS-CoV-2 on brain cells is not fully understood, highlighting the need for experimental models.
  • Researchers examined human induced pluripotent stem cell (hiPSC)-derived brain cells and organoids to assess their susceptibility to SARS-CoV-2 infection.
  • They found that certain brain cells, especially choroid plexus epithelial cells, were more significantly infected, leading to cell death and inflammatory responses, which supports the use of hiPSC-derived organoids for further research on the disease.
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Glioblastomas exhibit vast inter- and intra-tumoral heterogeneity, complicating the development of effective therapeutic strategies. Current in vitro models are limited in preserving the cellular and mutational diversity of parental tumors and require a prolonged generation time. Here, we report methods for generating and biobanking patient-derived glioblastoma organoids (GBOs) that recapitulate the histological features, cellular diversity, gene expression, and mutational profiles of their corresponding parental tumors.

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The thalamus, a crucial regulator of cortical functions, is composed of many nuclei arranged in a spatially complex pattern. Thalamic neurogenesis occurs over a short period during mammalian embryonic development. These features have hampered the effort to understand how regionalization, cell divisions, and fate specification are coordinated and produce a wide array of nuclei that exhibit distinct patterns of gene expression and functions.

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N-methyladenosine (mA) affects multiple aspects of mRNA metabolism and regulates developmental transitions by promoting mRNA decay. Little is known about the role of mA in the adult mammalian nervous system. Here we report that sciatic nerve lesion elevates levels of mA-tagged transcripts encoding many regeneration-associated genes and protein translation machinery components in the adult mouse dorsal root ganglion (DRG).

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Himantura signifer is a freshwater stingray which inhabits rivers in Southeast Asia. It can survive in brackish water but not seawater. In brackish water, it becomes partially ureosmotic, but how it maintains its plasma hypoionic to the external medium is enigmatic because of the lack of a rectal gland.

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L-gulono-γ-lactone oxidase (Gulo) catalyzes the last step of ascorbic acid biosynthesis, which occurs in the kidney of elasmobranchs. This study aimed to clone and sequence gulonolactone oxidase (gulo) from the kidney of the euryhaline freshwater stingray, Himantura signifer, and to determine the effects of acclimation from freshwater to brackish water (salinity 20) on its renal gulo mRNA expression and Gulo activity. We also examined the effects of brackish water acclimation on concentrations of ascorbate, dehydroascorbate and ascorbate + dehydroascorbate in the kidney, brain and gill.

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