Insight
is our reward
Search

Publications in Developmental Biology by NOMIS researchers

Cell-to-cell transmission of C9orf72 poly-(Gly-Ala) triggers key features of ALS/FTD

NOMIS Researcher(s)

Published in

April 15, 2020

The C9orf72 repeat expansion causes amyotrophic lateral sclerosis and frontotemporal dementia, but the poor correlation between C9orf72-specific pathology and TDP-43 pathology linked to neurodegeneration hinders targeted therapeutic development. Here, we addressed the role of the aggregating dipeptide repeat proteins resulting from unconventional translation of the repeat in all reading frames. Poly-GA promoted cytoplasmic mislocalization and aggregation of TDP-43 non-cell-autonomously, and anti-GA antibodies ameliorated TDP-43 mislocalization in both donor and receiver cells. Cell-to-cell transmission of poly-GA inhibited proteasome function in neighboring cells. Importantly, proteasome inhibition led to the accumulation of TDP-43 ubiquitinated within the nuclear localization signal (NLS) at lysine 95. Mutagenesis of this ubiquitination site completely blocked poly-GA-dependent mislocalization of TDP-43. Boosting proteasome function with rolipram reduced both poly-GA and TDP-43 aggregation. Our data from cell lines, primary neurons, transgenic mice, and patient tissue suggest that poly-GA promotes TDP-43 aggregation by inhibiting the proteasome cell-autonomously and non-cell-autonomously, which can be prevented by inhibiting poly-GA transmission with antibodies or boosting proteasome activity with rolipram.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.15252/embj.2019102811

Phase separation directs ubiquitination of gene-body nucleosomes

NOMIS Researcher(s)

Published in

March 26, 2020

The conserved yeast E3 ubiquitin ligase Bre1 and its partner, the E2 ubiquitin-conjugating enzyme Rad6, monoubiquitinate histone H2B across gene bodies during the transcription cycle1. Although processive ubiquitination might—in principle—arise from Bre1 and Rad6 travelling with RNA polymerase II2, the mechanism of H2B ubiquitination across genic nucleosomes remains unclear. Here we implicate liquid–liquid phase separation3 as the underlying mechanism. Biochemical reconstitution shows that Bre1 binds the scaffold protein Lge1, which possesses an intrinsically disordered region that phase-separates via multivalent interactions. The resulting condensates comprise a core of Lge1 encapsulated by an outer catalytic shell of Bre1. This layered liquid recruits Rad6 and the nucleosomal substrate, which accelerates the ubiquitination of H2B. In vivo, the condensate-forming region of Lge1 is required to ubiquitinate H2B in gene bodies beyond the +1 nucleosome. Our data suggest that layered condensates of histone-modifying enzymes generate chromatin-associated ‘reaction chambers’, with augmented catalytic activity along gene bodies. Equivalent processes may occur in human cells, and cause neurological disease when impaired.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1038/s41586-020-2097-z

A Genome-wide ER-phagy Screen Highlights Key Roles of Mitochondrial Metabolism and ER-Resident UFMylation

NOMIS Researcher(s)

Published in

March 19, 2020

Selective autophagy of organelles is critical for cellular differentiation, homeostasis, and organismal health. Autophagy of the ER (ER-phagy) is implicated in human neuropathy but is poorly understood beyond a few autophagosomal receptors and remodelers. By using an ER-phagy reporter and genome-wide CRISPRi screening, we identified 200 high-confidence human ER-phagy factors. Two pathways were unexpectedly required for ER-phagy. First, reduced mitochondrial metabolism represses ER-phagy, which is opposite of general autophagy and is independent of AMPK. Second, ER-localized UFMylation is required for ER-phagy to repress the unfolded protein response via IRE1α. The UFL1 ligase is brought to the ER surface by DDRGK1 to UFMylate RPN1 and RPL26 and preferentially targets ER sheets for degradation, analogous to PINK1-Parkin regulation during mitophagy. Our data provide insight into the cellular logic of ER-phagy, reveal parallels between organelle autophagies, and provide an entry point to the relatively unexplored process of degrading the ER network.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.cell.2020.02.017

Knocking out C9ORF72 Exacerbates Axonal Trafficking Defects Associated with Hexanucleotide Repeat Expansion and Reduces Levels of Heat Shock Proteins

NOMIS Researcher(s)

Published in

March 10, 2020

In amyotrophic lateral sclerosis (ALS) motor neurons (MNs) undergo dying-back, where the distal axon degenerates before the soma. The hexanucleotide repeat expansion (HRE) in C9ORF72 is the most common genetic cause of ALS, but the mechanism of pathogenesis is largely unknown with both gain- and loss-of-function mechanisms being proposed. To better understand C9ORF72-ALS pathogenesis, we generated isogenic induced pluripotent stem cells. MNs with HRE in C9ORF72 showed decreased axonal trafficking compared with gene corrected MNs. However, knocking out C9ORF72 did not recapitulate these changes in MNs from healthy controls, suggesting a gain-of-function mechanism. In contrast, knocking out C9ORF72 in MNs with HRE exacerbated axonal trafficking defects and increased apoptosis as well as decreased levels of HSP70 and HSP40, and inhibition of HSPs exacerbated ALS phenotypes in MNs with HRE. Therefore, we propose that the HRE in C9ORF72 induces ALS pathogenesis via a combination of gain- and loss-of-function mechanisms. Sterneckert and colleagues generated isogenic induced pluripotent stem cell lines and demonstrated that MNs with hexanucleotide repeat expansion (HRE) in C9ORF72 show reduced axonal trafficking, which is not recapitulated by knocking out C9ORF72 in MNs from healthy individuals. In contrast, knocking out C9ORF72 exacerbated phenotypes in MNs with HRE, suggesting that both gain- and loss-of-function mechanisms contribute to C9ORF72-ALS.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.stemcr.2020.01.010

Fully automated, sequential focused ion beam milling for cryo-electron tomography

NOMIS Researcher(s)

Published in

March 1, 2020

Cryo-electron tomography (cryoET) has become a powerful technique at the interface of structural biology and cell biology, due to its unique ability for imaging cells in their native state and determining structures of macromolecular complexes in their cellular context. A limitation of cryoET is its restriction to relatively thin samples. Sample thinning by cryo-focused ion beam (cryoFIB) milling has significantly expanded the range of samples that can be analyzed by cryoET. Unfortunately, cryoFIB milling is low-throughput, time-consuming and manual. Here, we report a method for fully automated sequential cryoFIB preparation of high-quality lamellae, including rough milling and polishing. We reproducibly applied this method to eukaryotic and bacterial model organisms, and show that the resulting lamellae are suitable for cryoET imaging and subtomogram averaging. Since our method reduces the time required for lamella preparation and minimizes the need for user input, we envision the technique will render previously inaccessible projects feasible.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.7554/eLife.52286

Active poly-GA vaccination prevents microglia activation and motor deficits in a C9orf72 mouse model

NOMIS Researcher(s)

Published in

February 7, 2020

The C9orf72 repeat expansion is the most common genetic cause of amyotrophic lateral sclerosis (ALS) and/or frontotemporal dementia (FTD). Non-canonical translation of the expanded repeat results in abundant poly-GA inclusion pathology throughout the CNS. (GA)149-CFP expression in mice triggers motor deficits and neuroinflammation. Since poly-GA is transmitted between cells, we investigated the therapeutic potential of anti-GA antibodies by vaccinating (GA)149-CFP mice. To overcome poor immunogenicity, we compared the antibody response of multivalent ovalbumin-(GA)10 conjugates and pre-aggregated carrier-free (GA)15. Only ovalbumin-(GA)10 immunization induced a strong anti-GA response. The resulting antisera detected poly-GA aggregates in cell culture and patient tissue. Ovalbumin-(GA)10 immunization largely rescued the motor function in (GA)149-CFP transgenic mice and reduced poly-GA inclusions. Transcriptome analysis showed less neuroinflammation in ovalbumin-(GA)10-immunized poly-GA mice, which was corroborated by semiquantitative and morphological analysis of microglia/macrophages. Moreover, cytoplasmic TDP-43 mislocalization and levels of the neurofilament light chain in the CSF were reduced, suggesting neuroaxonal damage is reduced. Our data suggest that immunotherapy may be a viable primary prevention strategy for ALS/FTD in C9orf72 mutation carriers.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.15252/emmm.201910919

Nup93 regulates breast tumor growth by modulating cell proliferation and actin cytoskeleton remodeling

NOMIS Researcher(s)

Published in

January 20, 2020

Nucleoporin 93 (Nup93) expression inversely correlates with the survival of triple-negative breast cancer patients. However, our knowledge of Nup93 function in breast cancer besides its role as structural component of the nuclear pore complex is not understood. Combination of functional assays and genetic analyses suggested that chromatin interaction of Nup93 partially modulates the expression of genes associated with actin cytoskeleton remodeling and epithelial to mesenchymal transition, resulting in impaired invasion of triple-negative, claudin-low breast cancer cells. Nup93 depletion induced stress fiber formation associated with reduced cell migration/proliferation and impaired expression of mesenchymal-like genes. Silencing LIMCH1, a gene responsible for actin cytoskeleton remodeling and up-regulated upon Nup93 depletion, partially restored the invasive phenotype of cancer cells. Loss of Nup93 led to significant defects in tumor establishment/propagation in vivo, whereas patient samples revealed that high Nup93 and low LIMCH1 expression correlate with late tumor stage. Our approach identified Nup93 as contributor of triple-negative, claudin-low breast cancer cell invasion and paves the way to study the role of nuclear envelope proteins during breast cancer tumorigenesis.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.26508/LSA.201900623

Punishing the individual or the group for norm violation

NOMIS Researcher(s)

Published in

January 1, 2020

Background: It has recently been proposed that a key motivation for joining groups is the protection from consequences of negative behaviours, such as norm violations. Here we empirically test this claim by investigating whether cooperative decisions and the punishment of associated fairness-based norm violations are different in individuals vs. collectives in economic games. Methods: In the ultimatum game, participants made or received offers that they could reject at a cost to their outcome, a form of social punishment. In the dictator game with third-party punishment, participants made offers to a receiver while being observed by a punisher, or could themselves punish unfair offers. Results: Participants made lower offers when making their decision as part of a group as compared to alone. This difference correlated with participants’ overall mean offers: those who were generally less generous were even less so in a group, suggesting that the collective structure was compatible with their intention. Participants were slower when punishing vs not punishing an unfair offer. Importantly here, they were slower when deciding whether to punish or not to punish groups as compared to individuals, only when the offer concerned them directly in second party punishment. Participants thus take more time to punish others, and to make their mind on whether to punish or not when facing a group of proposers. Conclusions: Together, these results show that people behave differently in a group, both in their willingness to share with others and in their punishment of norm violations. This could be explained by the fact that being in a collective structure allows to share responsibility with others, thereby protecting from negative consequences of norm violations.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.12688/wellcomeopenres.15474.1

Quantitative In Vivo Proteomics of Metformin Response in Liver Reveals AMPK-Dependent and -Independent Signaling Networks

NOMIS Researcher(s)

Published in

December 3, 2019

Metformin is the front-line treatment for type 2 diabetes worldwide. It acts via effects on glucose and lipid metabolism in metabolic tissues, leading to enhanced insulin sensitivity. Despite significant effort, the molecular basis for metformin response remains poorly understood, with a limited number of specific biochemical pathways studied to date. To broaden our understanding of hepatic metformin response, we combine phospho-protein enrichment in tissue from genetically engineered mice with a quantitative proteomics platform to enable the discovery and quantification of basophilic kinase substrates in vivo. We define proteins whose binding to 14-3-3 are acutely regulated by metformin treatment and/or loss of the serine/threonine kinase, LKB1. Inducible binding of 250 proteins following metformin treatment is observed, 44% of which proteins bind in a manner requiring LKB1. Beyond AMPK, metformin activates protein kinase D and MAPKAPK2 in an LKB1-independent manner, revealing additional kinases that may mediate aspects of metformin response. Deeper analysis uncovered substrates of AMPK in endocytosis and calcium homeostasis.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.celrep.2019.10.117

Septins organize endoplasmic reticulum-plasma membrane junctions for STIM1-ORAI1 calcium signalling

NOMIS Researcher(s)

Published in

December 1, 2019

ORAI1 Ca2+ channels in the plasma membrane (PM) are gated by STIM1 at endoplasmic reticulum (ER)-PM junctions to effect store-dependent Ca2+ entry into cells, but little is known about how local STIM-ORAI signalling at junctions is coordinated with overall cellular architecture. Filamentous septins can specify cytoskeletal rearrangements and have been found recently to modulate STIM-ORAI signalling. Here we show by super-resolution imaging of ORAI1, STIM1, and septin 4 in living cells that septins facilitate Ca2+ signalling indirectly. Septin 4 does not colocalize preferentially with ORAI1 in resting or stimulated cells, assemble stably at ER-PM junctions, or specify a boundary that directs or confines ORAI1 to junctions. Rather, ORAI1 is recruited to junctions solely through interaction with STIM proteins, while septins regulate the number of ER-PM junctions and enhance STIM1-ORAI1 interactions within junctions. Thus septins communicate with STIM1 and ORAI1 through protein or lipid intermediaries, and are favorably positioned to coordinate Ca2+ signalling with rearrangements in cellular architecture.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1038/s41598-019-46862-w

Simultaneous precise editing of multiple genes in human cells

NOMIS Researcher(s)

Published in

November 4, 2019

When double-strand breaks are introduced in a genome by CRISPR they are repaired either by non-homologous end joining (NHEJ), which often results in insertions or deletions (indels), or by homology-directed repair (HDR), which allows precise nucleotide substitutions to be introduced if a donor oligonucleotide is provided. Because NHEJ is more efficient than HDR, the frequency with which precise genome editing can be achieved is so low that simultaneous editing of more than one gene has hitherto not been possible. Here, we introduced a mutation in the human PRKDC gene that eliminates the kinase activity of the DNA-dependent protein kinase catalytic subunit (DNA-PKcs). This results in an increase in HDR irrespective of cell type and CRISPR enzyme used, sometimes allowing 87% of chromosomes in a population of cells to be precisely edited. It also allows for precise editing of up to four genes simultaneously (8 chromosomes) in the same cell. Transient inhibition of DNA-PKcs by the kinase inhibitor M3814 is similarly able to enhance precise genome editing.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1093/NAR/GKZ669

The mesoSPIM initiative: open-source light-sheet microscopes for imaging cleared tissue

NOMIS Researcher(s)

Published in

November 1, 2019

Light-sheet microscopy is an ideal technique for imaging large cleared samples; however, the community is still lacking instruments capable of producing volumetric images of centimeter-sized cleared samples with near-isotropic resolution within minutes. Here, we introduce the mesoscale selective plane-illumination microscopy initiative, an open-hardware project for building and operating a light-sheet microscope that addresses these challenges and is compatible with any type of cleared or expanded sample (www.mesospim.org).

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1038/s41592-019-0554-0

Organoid single-cell genomic atlas uncovers human-specific features of brain development

NOMIS Researcher(s)

Published in

October 17, 2019

The human brain has undergone substantial change since humans diverged from chimpanzees and the other great apes1,2. However, the genetic and developmental programs that underlie this divergence are not fully understood. Here we have analysed stem cell-derived cerebral organoids using single-cell transcriptomics and accessible chromatin profiling to investigate gene-regulatory changes that are specific to humans. We first analysed cell composition and reconstructed differentiation trajectories over the entire course of human cerebral organoid development from pluripotency, through neuroectoderm and neuroepithelial stages, followed by divergence into neuronal fates within the dorsal and ventral forebrain, midbrain and hindbrain regions. Brain-region composition varied in organoids from different iPSC lines, but regional gene-expression patterns remained largely reproducible across individuals. We analysed chimpanzee and macaque cerebral organoids and found that human neuronal development occurs at a slower pace relative to the other two primates. Using pseudotemporal alignment of differentiation paths, we found that human-specific gene expression resolved to distinct cell states along progenitor-to-neuron lineages in the cortex. Chromatin accessibility was dynamic during cortex development, and we identified divergence in accessibility between human and chimpanzee that correlated with human-specific gene expression and genetic change. Finally, we mapped human-specific expression in adult prefrontal cortex using single-nucleus RNA sequencing analysis and identified developmental differences that persist into adulthood, as well as cell-state-specific changes that occur exclusively in the adult brain. Our data provide a temporal cell atlas of great ape forebrain development, and illuminate dynamic gene-regulatory features that are unique to humans.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1038/s41586-019-1654-9

Robotic platform for microinjection into single cells in brain tissue

NOMIS Researcher(s)

Published in

October 4, 2019

Microinjection into single cells in brain tissue is a powerful technique to study and manipulate neural stem cells. However, such microinjection requires expertise and is a low-throughput process. We developed the “Autoinjector”, a robot that utilizes images from a microscope to guide a microinjection needle into tissue to deliver femtoliter volumes of liquids into single cells. The Autoinjector enables microinjection of hundreds of cells within a single organotypic slice, resulting in an overall yield that is an order of magnitude greater than manual microinjection. The Autoinjector successfully targets both apical progenitors (APs) and newborn neurons in the embryonic mouse and human fetal telencephalon. We used the Autoinjector to systematically study gap-junctional communication between neural progenitors in the embryonic mouse telencephalon and found that apical contact is a characteristic feature of the cells that are part of a gap junction-coupled cluster. The throughput and versatility of the Autoinjector will render microinjection an accessible high-performance single-cell manipulation technique and will provide a powerful new platform for performing single-cell analyses in tissue for bioengineering and biophysics applications.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.15252/embr.201947880

Proteomics of Melanoma Response to Immunotherapy Reveals Mitochondrial Dependence

NOMIS Researcher(s)

Published in

September 19, 2019

Proteomic profiling of melanomas from patients undergoing immunotherapy reveals key mediators of tumor immunogenicity.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.cell.2019.08.012

The MS4A gene cluster is a key modulator of soluble TREM2 and Alzheimer’s disease risk

NOMIS Researcher(s)

Published in

August 14, 2019

Soluble triggering receptor expressed on myeloid cells 2 (sTREM2) in cerebrospinal fluid (CSF) has been associated with Alzheimer’s disease (AD). TREM2 plays a critical role in microglial activation, survival, and phagocytosis; however, the pathophysiological role of sTREM2 in AD is not well understood. Understanding the role of sTREM2 in AD may reveal new pathological mechanisms and lead to the identification of therapeutic targets. We performed a genome-wide association study (GWAS) to identify genetic modifiers of CSF sTREM2 obtained from the Alzheimer’s Disease Neuroimaging Initiative. Common variants in the membrane-spanning 4-domains subfamily A (MS4A) gene region were associated with CSF sTREM2 concentrations (rs1582763; P = 1.15 × 10-15); this was replicated in independent datasets. The variants associated with increased CSF sTREM2 concentrations were associated with reduced AD risk and delayed age at onset of disease. The single-nucleotide polymorphism rs1582763 modified expression of the MS4A4A and MS4A6A genes in multiple tissues, suggesting that one or both of these genes are important for modulating sTREM2 production. Using human macrophages as a proxy for microglia, we found that MS4A4A and TREM2 colocalized on lipid rafts at the plasma membrane, that sTREM2 increased with MS4A4A overexpression, and that silencing of MS4A4A reduced sTREM2 production. These genetic, molecular, and cellular findings suggest that MS4A4A modulates sTREM2. These findings also provide a mechanistic explanation for the original GWAS signal in the MS4A locus for AD risk and indicate that TREM2 may be involved in AD pathogenesis not only in TREM2 risk-variant carriers but also in those with sporadic disease.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1126/scitranslmed.aau2291

Mutations in foregut SOX2+ cells induce efficient proliferation via CXCR2 pathway

NOMIS Researcher(s)

Published in

July 1, 2019

Identification of the precise molecular pathways involved in oncogene-induced transformation may help us gain a better understanding of tumor initiation and promotion. Here, we demonstrate that SOX2+ foregut epithelial cells are prone to oncogenic transformation upon mutagenic insults, such as KrasG12D and p53 deletion. GFP-based lineage-tracing experiments indicate that SOX2+ cells are the cells-of-origin of esophagus and stomach hyperplasia. Our observations indicate distinct roles for oncogenic KRAS mutation and P53 deletion. p53 homozygous deletion is required for the acquisition of an invasive potential, and KrasG12D expression, but not p53 deletion, suffices for tumor formation. Global gene expression analysis reveals secreting factors upregulated in the hyperplasia induced by oncogenic KRAS and highlights a crucial role for the CXCR2 pathway in driving hyperplasia. Collectively, the array of genetic models presented here demonstrate that stratified epithelial cells are susceptible to oncogenic insults, which may lead to a better understanding of tumor initiation and aid in the design of new cancer therapeutics.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1007/s13238-019-0630-3

Opposite microglial activation stages upon loss of PGRN or TREM2 result in reduced cerebral glucose metabolism

NOMIS Researcher(s)

Published in

June 1, 2019

Microglia adopt numerous fates with homeostatic microglia (HM) and a microglial neurodegenerative phenotype (MGnD) representing two opposite ends. A number of variants in genes selectively expressed in microglia are associated with an increased risk for neurodegenerative diseases such as Alzheimer’s disease (AD) and frontotemporal lobar degeneration (FTLD). Among these genes are progranulin (GRN) and the triggering receptor expressed on myeloid cells 2 (TREM2). Both cause neurodegeneration by mechanisms involving loss of function. We have now isolated microglia from Grn−/− mice and compared their transcriptomes to those of Trem2−/− mice. Surprisingly, while loss of Trem2 enhances the expression of genes associated with a homeostatic state, microglia derived from Grn−/− mice showed a reciprocal activation of the MGnD molecular signature and suppression of gene characteristic for HM. The opposite mRNA expression profiles are associated with divergent functional phenotypes. Although loss of TREM2 and progranulin resulted in opposite activation states and functional phenotypes of microglia, FDG (fluoro-2-deoxy-d-glucose)-μPET of brain revealed reduced glucose metabolism in both conditions, suggesting that opposite microglial phenotypes result in similar wide spread brain dysfunction.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.15252/emmm.201809711

The Solution Structure of FUS Bound to RNA Reveals a Bipartite Mode of RNA Recognition with Both Sequence and Shape Specificity

NOMIS Researcher(s)

Published in

February 7, 2019

FUS is an RNA binding protein associated with several neurodegenerative diseases, for which mode of nucleic acid binding has been elusive. Loughlin et al. solved the solution structure of FUS bound to RNA, revealing a sequence-specific recognition for a GGU motif and an unusual shape recognition of a stem loop by two separate domains.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.molcel.2018.11.012

Visualization of long-lived proteins reveals age mosaicism within nuclei of postmitotic cells

NOMIS Researcher(s)

Published in

February 1, 2019

Many adult tissues contain postmitotic cells as old as the host organism. Te only organelle that does not turn over in these cells is the nucleus, and its maintenance represents a formidable challenge, as it harbors regulatory proteins that persist throughout adulthood. Here we developed strategies to visualize two classes of such long-lived proteins, histones and nucleoporins, to understand the function of protein longevity in nuclear maintenance. Genome-wide mapping of histones revealed specifc enrichment of long-lived variants at silent gene loci. Interestingly, nuclear pores are maintained by piecemeal replacement of subunits, resulting in mosaic complexes composed of polypeptides with vastly different ages. In contrast, nondividing quiescent cells remove old nuclear pores in an ESCRT-dependent manner. Our fndings reveal distinct molecular strategies of nuclear maintenance, linking lifelong protein persistence to gene regulation and nuclear integrity.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1083/jcb.201809123

Neandertal Introgression Sheds Light on Modern Human Endocranial Globularity

NOMIS Researcher(s)

Published in

January 7, 2019

One of the features that distinguishes modern humans from our extinct relatives and ancestors is a globular shape of the braincase [1–4]. As the endocranium closely mirrors the outer shape of the brain, these differences might reflect altered neural architecture [4, 5]. However, in the absence of fossil brain tissue, the underlying neuroanatomical changes as well as their genetic bases remain elusive. To better understand the biological foundations of modern human endocranial shape, we turn to our closest extinct relatives: the Neandertals. Interbreeding between modern humans and Neandertals has resulted in introgressed fragments of Neandertal DNA in the genomes of present-day non-Africans [6, 7]. Based on shape analyses of fossil skull endocasts, we derive a measure of endocranial globularity from structural MRI scans of thousands of modern humans and study the effects of introgressed fragments of Neandertal DNA on this phenotype. We find that Neandertal alleles on chromosomes 1 and 18 are associated with reduced endocranial globularity. These alleles influence expression of two nearby genes, UBR4 and PHLPP1, which are involved in neurogenesis and myelination, respectively. Our findings show how integration of fossil skull data with archaic genomics and neuroimaging can suggest developmental mechanisms that may contribute to the unique modern human endocranial shape.

Research field(s)
Health Sciences, Biomedical Research, Developmental Biology

DOI
10.1016/j.cub.2018.10.065

Load More

  • NOMIS Foundation 2025
  • 2025 NOMIS Foundation