Multilayer and MATR3-dependent regulation of mRNAs maintains pluripotency in human induced pluripotent stem cells.

Matrin3 (MATR3) is a nuclear RNA/DNA-binding protein that plays pleiotropic roles in gene expression regulation by directly stabilizing target RNAs and supporting the activity of transcription factors by modulating chromatin architecture. MATR3 is involved in the differentiation of neural cells, and, here, we elucidate its critical functions in regulating pluripotent circuits in human induced pluripotent stem cells (hiPSCs). MATR3 downregulation affects hiPSCs' differentiation potential by altering key pluripotency regulators' expression levels, including OCT4, NANOG, and LIN28A by pleiotropic mechanisms.

Modeling medulloblastoma in vivo and with human cerebellar organoids.

Medulloblastoma (MB) is the most common malignant brain tumor in children and among the subtypes, Group 3 MB has the worst outcome. Here, we perform an in vivo, patient-specific screen leading to the identification of Otx2 and c-MYC as strong Group 3 MB inducers. We validated our findings in human cerebellar organoids where Otx2/c-MYC give rise to MB-like organoids harboring a DNA methylation signature that clusters with human Group 3 tumors.

Epsins Regulate Mouse Embryonic Stem Cell Exit from Pluripotency and Neural Commitment by Controlling Notch Activation.

Epsins are part of the internalization machinery pivotal to control clathrin-mediated endocytosis. Here, we report that epsin family members are expressed in mouse embryonic stem cells (mESCs) and that epsin1/2 knockdown alters both mESC exits from pluripotency and their differentiation. Furthermore, we show that epsin1/2 knockdown compromises the correct polarization and division of mESC-derived neural progenitors and their conversion into expandable radial glia-like neural stem cells.

Generation and characterization of a human iPSC line from an ALS patient carrying the Q66K-MATR3 mutation.

Fibroblasts isolated from an Amyotrophic Lateral Sclerosis (ALS)-patient carrying a mutation in Matrin-3 (p.Q66K -MATR3) gene were reprogrammed to the pluripotency stage by using non-integrating episomal plasmids. We generated the Q66K#44DRM induced pluripotent stem cell (iPSC) line that showed regular karyotype, expressed pluripotency-associated markers and were able to properly differentiate into the three germ layers.

mSEL-1L deficiency affects vasculogenesis and neural stem cell lineage commitment.

mSEL-1L is a highly conserved ER-resident type I protein, involved in the degradation of misfolded peptides through the ubiquitin-proteasome system (UPS), a pathway known to control the plasticity of the vascular smooth muscle cells (VSMC) phenotype and survival. In this article, we demonstrate that mSEL-1L deficiency interferes with the murine embryonic vascular network, showing particular irregularities in the intracranic and intersomitic neurovascular units and in the cerebral capillary microcirculation. During murine embryogenesis, mSEL-1L is expressed in cerebral areas known to harbor progenitor neural cells, while in the adult brain the protein is specifically restricted to the stem cell niches, co-localizing with Sox2 and Nestin.

Establishment of induced pluripotent stem cell (iPSC) line from an 8-year old female patient with ischemic Moyamoya disease.

Peripheral blood mononuclear cells (PBMCs) were collected from an 8-year old female patient affected by ischemic Moyamoya disease (MMD). Patient's PBMCs were reprogrammed using Sendai virus particles delivering the four Yamanaka factors. The footprint free hiPSC line expressed the major pluripotency markers and exhibited a normal karyotype.

Human pluripotent stem cells as tools for neurodegenerative and neurodevelopmental disease modeling and drug discovery.

Introduction: Although intensive efforts have been made, effective treatments for neurodegenerative and neurodevelopmental diseases have not been yet discovered. Possible reasons for this include the lack of appropriate disease models of human neurons and a limited understanding of the etiological and neurobiological mechanisms. Recent advances in pluripotent stem cell (PSC) research have now opened the path to the generation of induced pluripotent stem cells (iPSCs) starting from somatic cells, thus offering an unlimited source of patient-specific disease-relevant neuronal cells.

Cell and tissue microarray technologies for protein and nucleic acid expression profiling.

Tissue microarray (TMA) and cell microarray (CMA) are two powerful techniques that allow for the immunophenotypical characterization of hundreds of samples simultaneously. In particular, the CMA approach is particularly useful for immunophenotyping new stem cell lines (e.g.

Molecular chaperones as therapeutic targets to counteract proteostasis defects.

The health of cells is preserved by the levels and correct folding states of the proteome, which is generated and maintained by the proteostasis network, an integrated biological system consisting of several cytoprotective and degradative pathways. Indeed, the health conditions of the proteostasis network is a fundamental prerequisite to life as the inability to cope with the mismanagement of protein folding arising from genetic, epigenetic, and micro-environment stress appears to trigger a whole spectrum of unrelated diseases. Here we describe the potential functional role of the proteostasis network in tumor biology and in conformational diseases debating on how the signaling branches of this biological system may be manipulated to develop more efficacious and selective therapeutic strategies.

mSEL-1L (Suppressor/enhancer Lin12-like) protein levels influence murine neural stem cell self-renewal and lineage commitment.

Murine SEL-1L (mSEL-1L) is a key component of the endoplasmic reticulum-associated degradation pathway. It is essential during development as revealed by the multi-organ dysfunction and in uterus lethality occurring in homozygous mSEL-1L-deficient mice. Here we show that mSEL-1L is highly expressed in pluripotent embryonic stem cells and multipotent neural stem cells (NSCs) but silenced in all mature neural derivatives (i.

Deficiency of suppressor enhancer Lin12 1 like (SEL1L) in mice leads to systemic endoplasmic reticulum stress and embryonic lethality.

Stress in the endoplasmic reticulum (ER) plays an important causal role in the pathogenesis of several chronic diseases such as Alzheimer, Parkinson, and diabetes mellitus. Insight into the genetic determinants responsible for ER homeostasis will greatly facilitate the development of therapeutic strategies for the treatment of these debilitating diseases. Suppressor enhancer Lin12 1 like (SEL1L) is an ER membrane protein and was thought to be involved in the quality control of secreted proteins.

Functional characterization of two secreted SEL1L isoforms capable of exporting unassembled substrate.

SEL1L-A, a transmembrane glycoprotein residing in the endoplasmic reticulum (ER), is a component of the ER-associated degradation (ERAD) pathway. Alternative splicing generates two smaller SEL1L isoforms, -B and -C, that lack the SEL1L-A membrane-spanning region but retain some sel-1-like repeats, known to be involved in multi-protein interactions and signal transduction. In this study the functional characteristics of SEL1L-B and -C were investigated in human cell models.