Patricia Moran Losada

All Publications

• Proteostasis and lysosomal repair deficits in transdifferentiated neurons of Alzheimer's disease. Nature cell biology Chou, C. C., Vest, R., Prado, M. A., Wilson-Grady, J., Paulo, J. A., Shibuya, Y., Moran-Losada, P., Lee, T. T., Luo, J., Gygi, S. P., Kelly, J. W., Finley, D., Wernig, M., Wyss-Coray, T., Frydman, J. 2025

  Abstract

  Ageing is the most prominent risk factor for Alzheimer's disease (AD). However, the cellular mechanisms linking neuronal proteostasis decline to the characteristic aberrant protein deposits in the brains of patients with AD remain elusive. Here we develop transdifferentiated neurons (tNeurons) from human dermal fibroblasts as a neuronal model that retains ageing hallmarks and exhibits AD-linked vulnerabilities. Remarkably, AD tNeurons accumulate proteotoxic deposits, including phospho-tau and amyloid β, resembling those in APP mouse brains and the brains of patients with AD. Quantitative tNeuron proteomics identify ageing- and AD-linked deficits in proteostasis and organelle homeostasis, most notably in endosome-lysosomal components. Lysosomal deficits in aged tNeurons, including constitutive lysosomal damage and ESCRT-mediated lysosomal repair defects, are exacerbated in AD tNeurons and linked to inflammatory cytokine secretion and cell death. Providing support for the centrality of lysosomal deficits in AD, compounds ameliorating lysosomal function reduce amyloid β deposits and cytokine secretion. Thus, the tNeuron model system reveals impaired lysosomal homeostasis as an early event of ageing and AD.

  View details for DOI 10.1038/s41556-025-01623-y

  View details for PubMedID 40140603

  View details for PubMedCentralID 3521838

• Multi-tissue transcriptomic aging atlas reveals predictive aging biomarkers in the killifish. bioRxiv : the preprint server for biology Costa, E. K., Chen, J., Guldner, I. H., Mboning, L., Schmahl, N., Tsenter, A., Wu, M., Moran-Losada, P., Bouchard, L. S., Wang, S., Singh, P. P., Pellegrini, M., Brunet, A., Wyss-Coray, T. 2025

  Abstract

  Aging is associated with progressive tissue dysfunction, leading to frailty and mortality. Characterizing aging features, such as changes in gene expression and dynamics, shared across tissues or specific to each tissue, is crucial for understanding systemic and local factors contributing to the aging process. We performed RNA-sequencing on 13 tissues at 6 different ages in the African turquoise killifish, the shortest-lived vertebrate that can be raised in captivity. This comprehensive, sex-balanced 'atlas' dataset reveals the varying strength of sex-age interactions across killifish tissues and identifies age-altered biological pathways that are evolutionarily conserved. Demonstrating the utility of this resource, we discovered that the killifish head kidney exhibits a myeloid bias during aging, a phenomenon more pronounced in females than in males. In addition, we developed tissue-specific 'transcriptomic clocks' and identified biomarkers predictive of chronological age. We show the importance of sex-specific clocks for selected tissues and use the tissue clocks to evaluate a dietary intervention in the killifish. Our work provides a comprehensive resource for studying aging dynamics across tissues in the killifish, a powerful vertebrate aging model.

  View details for DOI 10.1101/2025.01.28.635350

  View details for PubMedID 39975269

• Proteostasis and lysosomal repair deficits in transdifferentiated neurons of Alzheimer's disease. bioRxiv : the preprint server for biology Chou, C. C., Vest, R., Prado, M. A., Wilson-Grady, J., Paulo, J. A., Shibuya, Y., Moran-Losada, P., Lee, T. T., Luo, J., Gygi, S. P., Kelly, J. W., Finley, D., Wernig, M., Wyss-Coray, T., Frydman, J. 2025

  Abstract

  Aging is the most prominent risk factor for Alzheimer's disease (AD). However, the cellular mechanisms linking neuronal proteostasis decline to the characteristic aberrant protein deposits in AD brains remain elusive. Here, we develop transdifferentiated neurons (tNeurons) from human dermal fibroblasts as a neuronal model that retains aging hallmarks and exhibits AD-linked vulnerabilities. Remarkably, AD tNeurons accumulate proteotoxic deposits, including phospho-Tau and Aβ, resembling those in AD patient and APP mouse brains. Quantitative tNeuron proteomics identify aging and AD-linked deficits in proteostasis and organelle homeostasis, most notably in endosome-lysosomal components. Lysosomal deficits in aged tNeurons, including constitutive lysosomal damage and ESCRT-mediated lysosomal repair defects, are exacerbated in AD tNeurons and linked to inflammatory cytokine secretion and cell death. Supporting lysosomal deficits' centrality in AD, compounds ameliorating lysosomal function reduce Aβ deposits and cytokine secretion. Thus, the tNeuron model system reveals impaired lysosomal homeostasis as an early event of aging and AD.

  View details for DOI 10.1101/2023.03.27.534444

  View details for PubMedID 37034684

  View details for PubMedCentralID PMC10081252

• Developing Topics. Alzheimer's & dementia : the journal of the Alzheimer's Association Latif-Hernandez, A., Iii, R. R., Moran-Losada, P., Yang, T., Tran, K. C., Liu, H., Wyss-Coray, T., Longo, F. M. 2024; 20 Suppl 8: e095712

  Abstract

  Activity-dependent transcription is crucial in establishing the late phase of long-term potentiation (L-LTP), which is altered in Alzheimer's disease (AD). TrkB and TrkC signaling-activator (BD10-2) reduces AD-related synaptic dysfunction. We determined whether the synapse-sparing effects of BD10-2 are reflected in transcriptional changes following L-LTP induction.We orally administered BD10-2 or vehicle to 13-month old APPL/S and WT mice, daily for 3 months. We measured L-LTP-dependent gene expression through RNA-sequencing in hippocampal slices with or without induction of Theta-Burst-Stimulation (TBS)-induced LTP.L-LTP induction failed in APPL/S-Veh but was restored in APPL/S-BD2-10 mice similarly to WT-veh. Analysis of overlap enrichment between mouse TBS-dependent gene expression and human AD-relevant modules, revealed: (1) greater downregulation of neuronal genes by TBS in WT-Veh and APPL/S-BD10-2 than in APPL/S-Veh; and (2) upregulation of microglial associated AD-enriched genes by TBS in all groups.BD10-2 prevented AD-related LTP deficits and restored activity-dependent AD-related gene transcription.

  View details for DOI 10.1002/alz.095712

  View details for PubMedID 39783201

• Human tNeurons reveal aging-linked proteostasis deficits driving Alzheimer's phenotypes. Research square Chou, C. C., Vest, R., Prado, M. A., Wilson-Grady, J., Paulo, J. A., Shibuya, Y., Moran-Losada, P., Lee, T. T., Luo, J., Gygi, S. P., Kelly, J. W., Finley, D., Wernig, M., Wyss-Coray, T., Frydman, J. 2024

  Abstract

  Aging is a prominent risk factor for Alzheimer's disease (AD), but the cellular mechanisms underlying neuronal phenotypes remain elusive. Both accumulation of amyloid plaques and neurofibrillary tangles in the brain1 and age-linked organelle deficits2-7 are proposed as causes of AD phenotypes but the relationship between these events is unclear. Here, we address this question using a transdifferentiated neuron (tNeuron) model directly from human dermal fibroblasts. Patient-derived tNeurons retain aging hallmarks and exhibit AD-linked deficits. Quantitative tNeuron proteomic analyses identify aging and AD-linked deficits in proteostasis and organelle homeostasis, particularly affecting endosome-lysosomal components. The proteostasis and lysosomal homeostasis deficits in aged tNeurons are exacerbated in sporadic and familial AD tNeurons, promoting constitutive lysosomal damage and defects in ESCRT-mediated repair. We find deficits in neuronal lysosomal homeostasis lead to inflammatory cytokine secretion, cell death and spontaneous development of Aß and phospho-Tau deposits. These proteotoxic inclusions co-localize with lysosomes and damage markers and resemble inclusions in brain tissue from AD patients and APP-transgenic mice. Supporting the centrality of lysosomal deficits driving AD phenotypes, lysosome-function enhancing compounds reduce AD-associated cytokine secretion and Aβ deposits. We conclude that proteostasis and organelle deficits are upstream initiating factors leading to neuronal aging and AD phenotypes.

  View details for DOI 10.21203/rs.3.rs-4407236/v1

  View details for PubMedID 38853828

  View details for PubMedCentralID PMC11160905

• Comprehensive proteomics of CSF, plasma, and urine identify DDC and other biomarkers of early Parkinson's disease. Acta neuropathologica Rutledge, J., Lehallier, B., Zarifkar, P., Losada, P. M., Shahid-Besanti, M., Western, D., Gorijala, P., Ryman, S., Yutsis, M., Deutsch, G. K., Mormino, E., Trelle, A., Wagner, A. D., Kerchner, G. A., Tian, L., Cruchaga, C., Henderson, V. W., Montine, T. J., Borghammer, P., Wyss-Coray, T., Poston, K. L. 2024; 147 (1): 52

  Abstract

  Parkinson's disease (PD) starts at the molecular and cellular level long before motor symptoms appear, yet there are no early-stage molecular biomarkers for diagnosis, prognosis prediction, or monitoring therapeutic response. This lack of biomarkers greatly impedes patient care and translational research-L-DOPA remains the standard of care more than 50 years after its introduction. Here, we performed a large-scale, multi-tissue, and multi-platform proteomics study to identify new biomarkers for early diagnosis and disease monitoring in PD. We analyzed 4877 cerebrospinal fluid, blood plasma, and urine samples from participants across seven cohorts using three orthogonal proteomics methods: Olink proximity extension assay, SomaScan aptamer precipitation assay, and liquid chromatography-mass spectrometry proteomics. We discovered that hundreds of proteins were upregulated in the CSF, blood, or urine of PD patients, prodromal PD patients with DAT deficit and REM sleep behavior disorder or anosmia, and non-manifesting genetic carriers of LRRK2 and GBA mutations. We nominate multiple novel hits across our analyses as promising markers of early PD, including DOPA decarboxylase (DDC), also known as L-aromatic acid decarboxylase (AADC), sulfatase-modifying factor 1 (SUMF1), dipeptidyl peptidase 2/7 (DPP7), glutamyl aminopeptidase (ENPEP), WAP four-disulfide core domain 2 (WFDC2), and others. DDC, which catalyzes the final step in dopamine synthesis, particularly stands out as a novel hit with a compelling mechanistic link to PD pathogenesis. DDC is consistently upregulated in the CSF and urine of treatment-naïve PD, prodromal PD, and GBA or LRRK2 carrier participants by all three proteomics methods. We show that CSF DDC levels correlate with clinical symptom severity in treatment-naïve PD patients and can be used to accurately diagnose PD and prodromal PD. This suggests that urine and CSF DDC could be a promising diagnostic and prognostic marker with utility in both clinical care and translational research.

  View details for DOI 10.1007/s00401-024-02706-0

  View details for PubMedID 38467937

  View details for PubMedCentralID 3995906

• Post-translational modifications linked to preclinical Alzheimer's disease-related pathological and cognitive changes. Alzheimer's & dementia : the journal of the Alzheimer's Association Abiose, O., Rutledge, J., Moran-Losada, P., Belloy, M. E., Wilson, E. N., He, Z., Trelle, A. N., Channappa, D., Romero, A., Park, J., Yutsis, M. V., Sha, S. J., Andreasson, K. I., Poston, K. L., Henderson, V. W., Wagner, A. D., Wyss-Coray, T., Mormino, E. C. 2023

  Abstract

  In this study, we leverage proteomic techniques to identify communities of proteins underlying Alzheimer's disease (AD) risk among clinically unimpaired (CU) older adults.We constructed a protein co-expression network using 3869 cerebrospinal fluid (CSF) proteins quantified by SomaLogic, Inc., in a cohort of participants along the AD clinical spectrum. We then replicated this network in an independent cohort of CU older adults and related these modules to clinically-relevant outcomes.We discovered modules enriched for phosphorylation and ubiquitination that were associated with abnormal amyloid status, as well as p-tau181 (M4: β = 2.44, p < 0.001, M7: β = 2.57, p < 0.001) and executive function performance (M4: β = -2.00, p = 0.005, M7: β = -2.39, p < 0.001).In leveraging CSF proteomic data from individuals spanning the clinical spectrum of AD, we highlight the importance of post-translational modifications for early cognitive and pathological changes.

  View details for DOI 10.1002/alz.13576

  View details for PubMedID 38146099

• Organ aging signatures in the plasma proteome track health and disease. Nature Oh, H. S., Rutledge, J., Nachun, D., Pálovics, R., Abiose, O., Moran-Losada, P., Channappa, D., Urey, D. Y., Kim, K., Sung, Y. J., Wang, L., Timsina, J., Western, D., Liu, M., Kohlfeld, P., Budde, J., Wilson, E. N., Guen, Y., Maurer, T. M., Haney, M., Yang, A. C., He, Z., Greicius, M. D., Andreasson, K. I., Sathyan, S., Weiss, E. F., Milman, S., Barzilai, N., Cruchaga, C., Wagner, A. D., Mormino, E., Lehallier, B., Henderson, V. W., Longo, F. M., Montgomery, S. B., Wyss-Coray, T. 2023; 624 (7990): 164-172

  Abstract

  Animal studies show aging varies between individuals as well as between organs within an individual1-4, but whether this is true in humans and its effect on age-related diseases is unknown. We utilized levels of human blood plasma proteins originating from specific organs to measure organ-specific aging differences in living individuals. Using machine learning models, we analysed aging in 11 major organs and estimated organ age reproducibly in five independent cohorts encompassing 5,676 adults across the human lifespan. We discovered nearly 20% of the population show strongly accelerated age in one organ and 1.7% are multi-organ agers. Accelerated organ aging confers 20-50% higher mortality risk, and organ-specific diseases relate to faster aging of those organs. We find individuals with accelerated heart aging have a 250% increased heart failure risk and accelerated brain and vascular aging predict Alzheimer's disease (AD) progression independently from and as strongly as plasma pTau-181 (ref. 5), the current best blood-based biomarker for AD. Our models link vascular calcification, extracellular matrix alterations and synaptic protein shedding to early cognitive decline. We introduce a simple and interpretable method to study organ aging using plasma proteomics data, predicting diseases and aging effects.

  View details for DOI 10.1038/s41586-023-06802-1

  View details for PubMedID 38057571

  View details for PubMedCentralID PMC10700136

• Transdifferentiation: A Novel Tool for Disease Modeling and Translational Applications in Alzheimer's Disease Chou, C., Vest, R., Prado, M. A., Wilson-Grady, J., Paulo, J. A., Shibuya, Y., Moran-Losada, P., Lee, T., Luo, J., Gygi, S. P., Kelly, J. W., Finley, D. P., Wernig, M., Wyss-Coray, T., Frydman, J. WILEY. 2023: S205-S206

  View details for Web of Science ID 001084474200356

• Atlas of the aging mouse brain reveals white matter as vulnerable foci. Cell Hahn, O., Foltz, A. G., Atkins, M., Kedir, B., Moran-Losada, P., Guldner, I. H., Munson, C., Kern, F., Pálovics, R., Lu, N., Zhang, H., Kaur, A., Hull, J., Huguenard, J. R., Grönke, S., Lehallier, B., Partridge, L., Keller, A., Wyss-Coray, T. 2023

  Abstract

  Aging is the key risk factor for cognitive decline, yet the molecular changes underlying brain aging remain poorly understood. Here, we conducted spatiotemporal RNA sequencing of the mouse brain, profiling 1,076 samples from 15 regions across 7 ages and 2 rejuvenation interventions. Our analysis identified a brain-wide gene signature of aging in glial cells, which exhibited spatially defined changes in magnitude. By integrating spatial and single-nucleus transcriptomics, we found that glial aging was particularly accelerated in white matter compared with cortical regions, whereas specialized neuronal populations showed region-specific expression changes. Rejuvenation interventions, including young plasma injection and dietary restriction, exhibited distinct effects on gene expression in specific brain regions. Furthermore, we discovered differential gene expression patterns associated with three human neurodegenerative diseases, highlighting the importance of regional aging as a potential modulator of disease. Our findings identify molecular foci of brain aging, providing a foundation to target age-related cognitive decline.

  View details for DOI 10.1016/j.cell.2023.07.027

  View details for PubMedID 37591239

• The Cystic Fibrosis Upper and Lower Airway Metagenome MICROBIOLOGY SPECTRUM Pienkowska, K., Pust, M., Gessner, M., Gaedcke, S., Thavarasa, A., Rosenboom, I., Moran Losada, P., Minso, R., Arnold, C., Hedtfeld, S., Dorda, M., Wiehlmann, L., Mainz, J. G., Klockgether, J., Tuemmler, B. 2023: e0363322

  Abstract

  The microbial metagenome in cystic fibrosis (CF) airways was investigated by whole-genome shotgun sequencing of total DNA isolated from nasal lavage samples, oropharyngeal swabs, and induced sputum samples collected from 65 individuals with CF aged 7 to 50 years. Each patient harbored a personalized microbial metagenome unique in microbial load and composition, the exception being monocultures of the most common CF pathogens Staphylococcus aureus and Pseudomonas aeruginosa from patients with advanced lung disease. The sampling of the upper airways by nasal lavage uncovered the fungus Malassezia restricta and the bacterium Staphylococcus epidermidis as prominent species. Healthy and CF donors harbored qualitatively and quantitatively different spectra of commensal bacteria in their sputa, even in the absence of any typical CF pathogen. If P. aeruginosa, S. aureus, or Stenotrophomonas maltophilia belonged to the trio of the most abundant species in the CF sputum metagenome, common inhabitants of the respiratory tract of healthy subjects, i.e., Eubacterium sulci, Fusobacterium periodonticum, and Neisseria subflava, were present only in low numbers or not detectable. Random forest analysis identified the numerical ecological parameters of the bacterial community, such as Shannon and Simpson diversity, as the key parameters that globally distinguish sputum samples from CF and healthy donors. IMPORTANCE Cystic fibrosis (CF) is the most common life-limiting monogenetic disease in European populations and is caused by mutations in the CFTR gene. Chronic airway infections with opportunistic pathogens are the major morbidity that determines prognosis and quality of life in most people with CF. We examined the composition of the microbial communities of the oral cavity and upper and lower airways in CF patients across all age groups. From early on, the spectrum of commensals is different in health and CF. Later on, when the common CF pathogens take up residence in the lungs, we observed differential modes of depletion of the commensal microbiota in the presence of S. aureus, P. aeruginosa, S. maltophilia, or combinations thereof. It remains to be seen whether the implementation of lifelong CFTR (cystic fibrosis transmembrane conductance regulator) modulation will change the temporal evolution of the CF airway metagenome.

  View details for DOI 10.1128/spectrum.03633-22

  View details for Web of Science ID 000946019000001

  View details for PubMedID 36892308

• Cerebrospinal fluid immune dysregulation during healthy brain aging and cognitive impairment. Cell Piehl, N., van Olst, L., Ramakrishnan, A., Teregulova, V., Simonton, B., Zhang, Z., Tapp, E., Channappa, D., Oh, H., Losada, P. M., Rutledge, J., Trelle, A. N., Mormino, E. C., Elahi, F., Galasko, D. R., Henderson, V. W., Wagner, A. D., Wyss-Coray, T., Gate, D. 2022

  Abstract

  Cerebrospinal fluid (CSF) contains a tightly regulated immune system. However, knowledge is lacking about how CSF immunity is altered with aging or neurodegenerative disease. Here, we performed single-cell RNA sequencing on CSF from 45 cognitively normal subjects ranging from 54 to 82 years old. We uncovered an upregulation of lipid transport genes in monocytes with age. We then compared this cohort with 14 cognitively impaired subjects. In cognitively impaired subjects, downregulation of lipid transport genes in monocytes occurred concomitantly with altered cytokine signaling to CD8 Tcells. Clonal CD8T effector memory cells upregulated C-X-C motif chemokine receptor 6 (CXCR6) in cognitively impaired subjects. The CXCR6 ligand, C-X-C motif chemokine ligand 16 (CXCL16), was elevated in the CSF of cognitively impaired subjects, suggesting CXCL16-CXCR6 signaling as a mechanism for antigen-specific Tcell entry into the brain. Cumulatively, these results reveal cerebrospinal fluid immune dysregulation during healthy brain aging and cognitive impairment.

  View details for DOI 10.1016/j.cell.2022.11.019

  View details for PubMedID 36516855

• An IL1RL1 genetic variant lowers soluble ST2 levels and the risk effects of APOE-ε4 in female patients with Alzheimer's disease. Nature aging Jiang, Y., Zhou, X., Wong, H. Y., Ouyang, L., Ip, F. C., Chau, V. M., Lau, S. F., Wu, W., Wong, D. Y., Seo, H., Fu, W. Y., Lai, N. C., Chen, Y., Chen, Y., Tong, E. P., Mok, V. C., Kwok, T. C., Mok, K. Y., Shoai, M., Lehallier, B., Losada, P. M., O'Brien, E., Porter, T., Laws, S. M., Hardy, J., Wyss-Coray, T., Masters, C. L., Fu, A. K., Ip, N. Y. 2022; 2 (7): 616-634

  Abstract

  Changes in the levels of circulating proteins are associated with Alzheimer's disease (AD), whereas their pathogenic roles in AD are unclear. Here, we identified soluble ST2 (sST2), a decoy receptor of interleukin-33-ST2 signaling, as a new disease-causing factor in AD. Increased circulating sST2 level is associated with more severe pathological changes in female individuals with AD. Genome-wide association analysis and CRISPR-Cas9 genome editing identified rs1921622 , a genetic variant in an enhancer element of IL1RL1, which downregulates gene and protein levels of sST2. Mendelian randomization analysis using genetic variants, including rs1921622 , demonstrated that decreased sST2 levels lower AD risk and related endophenotypes in females carrying the Apolipoprotein E (APOE)-ε4 genotype; the association is stronger in Chinese than in European-descent populations. Human and mouse transcriptome and immunohistochemical studies showed that rs1921622 /sST2 regulates amyloid-beta (Aβ) pathology through the modulation of microglial activation and Aβ clearance. These findings demonstrate how sST2 level is modulated by a genetic variation and plays a disease-causing role in females with AD.

  View details for DOI 10.1038/s43587-022-00241-9

  View details for PubMedID 37117777

  View details for PubMedCentralID 5958625

• A human brain vascular atlas reveals diverse mediators of Alzheimer's risk. Nature Yang, A. C., Vest, R. T., Kern, F., Lee, D. P., Agam, M., Maat, C. A., Losada, P. M., Chen, M. B., Schaum, N., Khoury, N., Toland, A., Calcuttawala, K., Shin, H., Palovics, R., Shin, A., Wang, E. Y., Luo, J., Gate, D., Schulz-Schaeffer, W. J., Chu, P., Siegenthaler, J. A., McNerney, M. W., Keller, A., Wyss-Coray, T. 2022

  Abstract

  The human brain vasculature is of great medical importance: its dysfunction causes disability and death1, and the specialized structure it forms-the blood-brain barrier-impedes the treatment of nearly all brain disorders2,3. Yet so far, we have no molecular map of the human brain vasculature. Here we develop vessel isolation and nuclei extraction for sequencing (VINE-seq) to profile the major vascular and perivascular cell types of the human brain through 143,793 single-nucleus transcriptomes from 25 hippocampus and cortex samples of 9 individuals with Alzheimer's disease and 8 individuals with no cognitive impairment. We identify brain-region- and species-enriched genes and pathways. We reveal molecular principles of human arteriovenous organization, recapitulating a gradual endothelial and punctuated mural cell continuum. We discover two subtypes of human pericytes, marked by solute transport and extracellular matrix (ECM) organization; and define perivascular versus meningeal fibroblast specialization. In Alzheimer's disease, we observe selective vulnerability of ECM-maintaining pericytes and gene expression patterns that implicate dysregulated blood flow. With an expanded survey of brain cell types, we find that 30 of the top 45 genes that have been linked to Alzheimer's diseaserisk by genome-wide association studies (GWASs) are expressed in the human brain vasculature, and we confirm this by immunostaining. Vascular GWAS genes map to endothelial protein transport, adaptive immune and ECM pathways. Many are microglia-specific in mice, suggesting a partial evolutionary transfer of Alzheimer's disease risk. Our work uncovers the molecular basis of the human brain vasculature, which will inform our understanding of overall brain health, disease and therapy.

  View details for DOI 10.1038/s41586-021-04369-3

  View details for PubMedID 35165441

• Cortical organoids model early brain development disrupted by 16p11.2 copy number variants in autism. Molecular psychiatry Urresti, J., Zhang, P., Moran-Losada, P., Yu, N. K., Negraes, P. D., Trujillo, C. A., Antaki, D., Amar, M., Chau, K., Pramod, A. B., Diedrich, J., Tejwani, L., Romero, S., Sebat, J., Yates Iii, J. R., Muotri, A. R., Iakoucheva, L. M. 2021; 26 (12): 7560-7580

  Abstract

  Reciprocal deletion and duplication of the 16p11.2 region is the most common copy number variation (CNV) associated with autism spectrum disorders. We generated cortical organoids from skin fibroblasts of patients with 16p11.2 CNV to investigate impacted neurodevelopmental processes. We show that organoid size recapitulates macrocephaly and microcephaly phenotypes observed in the patients with 16p11.2 deletions and duplications. The CNV dosage affects neuronal maturation, proliferation, and synapse number, in addition to its effect on organoid size. We demonstrate that 16p11.2 CNV alters the ratio of neurons to neural progenitors in organoids during early neurogenesis, with a significant excess of neurons and depletion of neural progenitors observed in deletions. Transcriptomic and proteomic profiling revealed multiple pathways dysregulated by the 16p11.2 CNV, including neuron migration, actin cytoskeleton, ion channel activity, synaptic-related functions, and Wnt signaling. The level of the active form of small GTPase RhoA was increased in both, deletions and duplications. Inhibition of RhoA activity rescued migration deficits, but not neurite outgrowth. This study provides insights into potential neurobiological mechanisms behind the 16p11.2 CNV during neocortical development.

  View details for DOI 10.1038/s41380-021-01243-6

  View details for PubMedID 34433918

  View details for PubMedCentralID PMC8873019

• Autism-linked Cullin3 germline haploinsufficiency impacts cytoskeletal dynamics and cortical neurogenesis through RhoA signaling. Molecular psychiatry Amar, M., Pramod, A. B., Yu, N. K., Herrera, V. M., Qiu, L. R., Moran-Losada, P., Zhang, P., Trujillo, C. A., Ellegood, J., Urresti, J., Chau, K., Diedrich, J., Chen, J., Gutierrez, J., Sebat, J., Ramanathan, D., Lerch, J. P., Yates, J. R., Muotri, A. R., Iakoucheva, L. M. 2021; 26 (7): 3586-3613

  Abstract

  E3-ubiquitin ligase Cullin3 (Cul3) is a high confidence risk gene for autism spectrum disorder (ASD) and developmental delay (DD). To investigate how Cul3 mutations impact brain development, we generated a haploinsufficient Cul3 mouse model using CRISPR/Cas9 genome engineering. Cul3 mutant mice exhibited social and cognitive deficits and hyperactive behavior. Brain MRI found decreased volume of cortical regions and changes in many other brain regions of Cul3 mutant mice starting from early postnatal development. Spatiotemporal transcriptomic and proteomic profiling of embryonic, early postnatal and adult brain implicated neurogenesis and cytoskeletal defects as key drivers of Cul3 functional impact. Specifically, dendritic growth, filamentous actin puncta, and spontaneous network activity were reduced in Cul3 mutant mice. Inhibition of small GTPase RhoA, a molecular substrate of Cul3 ligase, rescued dendrite length and network activity phenotypes. Our study identified defects in neuronal cytoskeleton and Rho signaling as the primary targets of Cul3 mutation during brain development.

  View details for DOI 10.1038/s41380-021-01052-x

  View details for PubMedID 33727673

  View details for PubMedCentralID PMC8443683

• Dysregulation of brain and choroid plexus cell types in severe COVID-19. Nature Yang, A. C., Kern, F., Losada, P. M., Agam, M. R., Maat, C. A., Schmartz, G. P., Fehlmann, T., Stein, J. A., Schaum, N., Lee, D. P., Calcuttawala, K., Vest, R. T., Berdnik, D., Lu, N., Hahn, O., Gate, D., McNerney, M. W., Channappa, D., Cobos, I., Ludwig, N., Schulz-Schaeffer, W. J., Keller, A., Wyss-Coray, T. 2021

  Abstract

  Though SARS-CoV-2 primarily targets the respiratory system, patients and survivors can suffer neurological symptoms1-3. Yet, an unbiased understanding of the cellular and molecular processes affected in the brains of COVID-19 patients is still missing. Here, we profile 65,309 single-nucleus transcriptomes from 30 frontal cortex and choroid plexus samples across 14 control (including 1 terminal influenza) and 8 COVID-19 patients. While a systematic analysis yields no molecular traces of SARS-CoV-2 in the brain, we observe broad cellular perturbations which predict that choroid plexus barrier cells sense and relay peripheral inflammation into the brain and show that peripheral T cells infiltrate the parenchyma. We discover COVID-19 disease-associated microglia and astrocyte subpopulations that share features with pathological cell states reported in human neurodegenerative disease4-6. Synaptic signaling of upper-layer excitatory neurons-evolutionarily expanded in humans7 and linked to cognitive function8-are preferentially affected in COVID-19. Across cell types, COVID-19 perturbations overlap with those in chronic brain disorders and reside in genetic variants associated with cognition, schizophrenia, and depression. Our findings and public dataset provide a molecular framework to understand COVID-19 related neurological disease observed now and which may emerge later.

  View details for DOI 10.1038/s41586-021-03710-0

  View details for PubMedID 34153974

• Genome-wide analysis of common and rare variants via multiple knockoffs at biobank scale, with an application to Alzheimer disease genetics. American journal of human genetics He, Z., Le Guen, Y., Liu, L., Lee, J., Ma, S., Yang, A. C., Liu, X., Rutledge, J., Losada, P. M., Song, B., Belloy, M. E., Butler, R. R., Longo, F. M., Tang, H., Mormino, E. C., Wyss-Coray, T., Greicius, M. D., Ionita-Laza, I. 2021

  Abstract

  Knockoff-based methods have become increasingly popular due to their enhanced power for locus discovery and their ability to prioritize putative causal variants in a genome-wide analysis. However, because of the substantial computational cost for generating knockoffs, existing knockoff approaches cannot analyze millions of rare genetic variants in biobank-scale whole-genome sequencing and whole-genome imputed datasets. We propose a scalable knockoff-based method for the analysis of common and rare variants across the genome, KnockoffScreen-AL, that is applicable to biobank-scale studies with hundreds of thousands of samples and millions of genetic variants. The application of KnockoffScreen-AL to the analysis of Alzheimer disease (AD) in 388,051 WG-imputed samples from the UK Biobank resulted in 31 significant loci, including 14 loci that are missed by conventional association tests on these data. We perform replication studies in an independent meta-analysis of clinically diagnosed AD with 94,437 samples, and additionally leverage single-cell RNA-sequencing data with 143,793 single-nucleus transcriptomes from 17 control subjects and AD-affected individuals, and proteomics data from 735 control subjects and affected indviduals with AD and related disorders to validate the genes at these significant loci. These multi-omics analyses show that 79.1% of the proximal genes at these loci and 76.2% of the genes at loci identified only by KnockoffScreen-AL exhibit at least suggestive signal (p < 0.05) in the scRNA-seq or proteomics analyses. We highlight a potentially causal gene in AD progression, EGFR, that shows significant differences in expression and protein levels between AD-affected individuals and healthy control subjects.

  View details for DOI 10.1016/j.ajhg.2021.10.009

  View details for PubMedID 34767756

• Ageing hallmarks exhibit organ-specific temporal signatures. Nature Schaum, N. n., Lehallier, B. n., Hahn, O. n., Pálovics, R. n., Hosseinzadeh, S. n., Lee, S. E., Sit, R. n., Lee, D. P., Losada, P. M., Zardeneta, M. E., Fehlmann, T. n., Webber, J. T., McGeever, A. n., Calcuttawala, K. n., Zhang, H. n., Berdnik, D. n., Mathur, V. n., Tan, W. n., Zee, A. n., Tan, M. n., Pisco, A. O., Karkanias, J. n., Neff, N. F., Keller, A. n., Darmanis, S. n., Quake, S. R., Wyss-Coray, T. n. 2020

  Abstract

  Ageing is the single greatest cause of disease and death worldwide, and understanding the associated processes could vastly improve quality of life. Although major categories of ageing damage have been identified-such as altered intercellular communication, loss of proteostasis and eroded mitochondrial function1-these deleterious processes interact with extraordinary complexity within and between organs, and a comprehensive, whole-organism analysis of ageing dynamics has been lacking. Here we performed bulk RNA sequencing of 17 organs and plasma proteomics at 10 ages across the lifespan of Mus musculus, and integrated these findings with data from the accompanying Tabula Muris Senis2-or 'Mouse Ageing Cell Atlas'-which follows on from the original Tabula Muris3. We reveal linear and nonlinear shifts in gene expression during ageing, with the associated genes clustered in consistent trajectory groups with coherent biological functions-including extracellular matrix regulation, unfolded protein binding, mitochondrial function, and inflammatory and immune response. Notably, these gene sets show similar expression across tissues, differing only in the amplitude and the age of onset of expression. Widespread activation of immune cells is especially pronounced, and is first detectable in white adipose depots during middle age. Single-cell RNA sequencing confirms the accumulation of T cells and B cells in adipose tissue-including plasma cells that express immunoglobulin J-which also accrue concurrently across diverse organs. Finally, we show how gene expression shifts in distinct tissues are highly correlated with corresponding protein levels in plasma, thus potentially contributing to the ageing of the systemic circulation. Together, these data demonstrate a similar yet asynchronous inter- and intra-organ progression of ageing, providing a foundation from which to track systemic sources of declining health at old age.

  View details for DOI 10.1038/s41586-020-2499-y

  View details for PubMedID 32669715

• Undulating changes in human plasma proteome profiles across the lifespan. Nature medicine Lehallier, B. n., Gate, D. n., Schaum, N. n., Nanasi, T. n., Lee, S. E., Yousef, H. n., Moran Losada, P. n., Berdnik, D. n., Keller, A. n., Verghese, J. n., Sathyan, S. n., Franceschi, C. n., Milman, S. n., Barzilai, N. n., Wyss-Coray, T. n. 2019; 25 (12): 1843–50

  Abstract

  Aging is a predominant risk factor for several chronic diseases that limit healthspan1. Mechanisms of aging are thus increasingly recognized as potential therapeutic targets. Blood from young mice reverses aspects of aging and disease across multiple tissues2-10, which supports a hypothesis that age-related molecular changes in blood could provide new insights into age-related disease biology. We measured 2,925 plasma proteins from 4,263 young adults to nonagenarians (18-95 years old) and developed a new bioinformatics approach that uncovered marked non-linear alterations in the human plasma proteome with age. Waves of changes in the proteome in the fourth, seventh and eighth decades of life reflected distinct biological pathways and revealed differential associations with the genome and proteome of age-related diseases and phenotypic traits. This new approach to the study of aging led to the identification of unexpected signatures and pathways that might offer potential targets for age-related diseases.

  View details for DOI 10.1038/s41591-019-0673-2

  View details for PubMedID 31806903

• Transcriptome-wide isoform-level dysregulation in ASD, schizophrenia, and bipolar disorder SCIENCE Gandal, M. J., Zhang, P., Hadjimichael, E., Walker, R. L., Chen, C., Liu, S., Won, H., van Bakel, H., Varghese, M., Wang, Y., Shieh, A. W., Haney, J., Parhami, S., Belmont, J., Kim, M., Losada, P., Khan, Z., Mleczko, J., Xia, Y., Dai, R., Wang, D., Yang, Y. T., Xu, M., Fish, K., Hof, P. R., Warrell, J., Fitzgerald, D., White, K., Jaffe, A. E., Peters, M. A., Gerstein, M., Liu, C., Iakoucheva, L. M., Pinto, D., Geschwind, D. H., PsychENCODE Consortium 2018; 362 (6420): 1265-+

  Abstract

  Most genetic risk for psychiatric disease lies in regulatory regions, implicating pathogenic dysregulation of gene expression and splicing. However, comprehensive assessments of transcriptomic organization in diseased brains are limited. In this work, we integrated genotypes and RNA sequencing in brain samples from 1695 individuals with autism spectrum disorder (ASD), schizophrenia, and bipolar disorder, as well as controls. More than 25% of the transcriptome exhibits differential splicing or expression, with isoform-level changes capturing the largest disease effects and genetic enrichments. Coexpression networks isolate disease-specific neuronal alterations, as well as microglial, astrocyte, and interferon-response modules defining previously unidentified neural-immune mechanisms. We integrated genetic and genomic data to perform a transcriptome-wide association study, prioritizing disease loci likely mediated by cis effects on brain expression. This transcriptome-wide characterization of the molecular pathology across three major psychiatric disorders provides a comprehensive resource for mechanistic insight and therapeutic development.

  View details for DOI 10.1126/science.aat8127

  View details for Web of Science ID 000452994400042

  View details for PubMedID 30545856

  View details for PubMedCentralID PMC6443102

• Filtration and Normalization of Sequencing Read Data in Whole-Metagenome Shotgun Samples PLOS ONE Chouvarine, P., Wiehlmann, L., Losada, P., DeLuca, D. S., Tuemmler, B. 2016; 11 (10): e0165015

  Abstract

  Ever-increasing affordability of next-generation sequencing makes whole-metagenome sequencing an attractive alternative to traditional 16S rDNA, RFLP, or culturing approaches for the analysis of microbiome samples. The advantage of whole-metagenome sequencing is that it allows direct inference of the metabolic capacity and physiological features of the studied metagenome without reliance on the knowledge of genotypes and phenotypes of the members of the bacterial community. It also makes it possible to overcome problems of 16S rDNA sequencing, such as unknown copy number of the 16S gene and lack of sufficient sequence similarity of the "universal" 16S primers to some of the target 16S genes. On the other hand, next-generation sequencing suffers from biases resulting in non-uniform coverage of the sequenced genomes. To overcome this difficulty, we present a model of GC-bias in sequencing metagenomic samples as well as filtration and normalization techniques necessary for accurate quantification of microbial organisms. While there has been substantial research in normalization and filtration of read-count data in such techniques as RNA-seq or Chip-seq, to our knowledge, this has not been the case for the field of whole-metagenome shotgun sequencing. The presented methods assume that complete genome references are available for most microorganisms of interest present in metagenomic samples. This is often a valid assumption in such fields as medical diagnostics of patient microbiota. Testing the model on two validation datasets showed four-fold reduction in root-mean-square error compared to non-normalized data in both cases. The presented methods can be applied to any pipeline for whole metagenome sequencing analysis relying on complete microbial genome references. We demonstrate that such pre-processing reduces the number of false positive hits and increases accuracy of abundance estimates.

  View details for DOI 10.1371/journal.pone.0165015

  View details for Web of Science ID 000386204000075

  View details for PubMedID 27760173

  View details for PubMedCentralID PMC5070866

• SNP synteny analysis of Staphylococcus aureus and Pseudomonas aeruginosa population genomics FEMS MICROBIOLOGY LETTERS Losada, P., Tuemmler, B. 2016; 363 (19)

  View details for DOI 10.1093/femsle/fnw229

  View details for Web of Science ID 000388381800015

• Three-base periodicity of sites of sequence variation in Pseudomonas aeruginosa and Staphylococcus aureus core genomes. FEBS letters Morán Losada, P., Fischer, S., Chouvarine, P., Tümmler, B. 2016; 590 (20): 3538-3543

  Abstract

  The three-base periodicity property is characteristic of protein-coding sequences. Here, we report on three-base periodicity of sequence variation in the core genome of bacteria. Single nucleotide polymorphism (SNP) syntenies were extracted from pairwise genome alignments of 41 Staphylococcus aureus or 20 Pseudomonas aeruginosa strains. The length of fragment pairs with identical nucleotides at all SNP positions showed a length-dependent overrepresentation of multiples of three nucleotides at corresponding codon positions of the AT-rich S. aureus and the GC-rich P. aeruginosa. Three-base SNP periodicity seems to be a characteristic feature of the tightly arranged bacterial core genome.

  View details for DOI 10.1002/1873-3468.12431

  View details for PubMedID 27664047

• Intraclonal genome diversity of the major Pseudomonas aeruginosa clones C and PA14 ENVIRONMENTAL MICROBIOLOGY REPORTS Fischer, S., Klockgether, J., Losada, P., Chouvarine, P., Cramer, N., Davenport, C. F., Dethlefsen, S., Dorda, M., Goesmann, A., Hilker, R., Mielke, S., Schoenfelder, T., Suerbaum, S., Tuerk, O., Woltemate, S., Wiehlmann, L., Tuemmler, B. 2016; 8 (2): 227–34

  Abstract

  Bacterial populations differentiate at the subspecies level into clonal complexes. Intraclonal genome diversity was studied in 100 isolates of the two dominant Pseudomonas aeruginosa clones C and PA14 collected from the inanimate environment, acute and chronic infections. The core genome was highly conserved among clone members with a median pairwise within-clone single nucleotide sequence diversity of 8 × 10(-6) for clone C and 2 × 10(-5) for clone PA14. The composition of the accessory genome was, on the other hand, as variable within the clone as between unrelated clones. Each strain carried a large cargo of unique genes. The two dominant worldwide distributed P. aeruginosa clones combine an almost invariant core with the flexible gain and loss of genetic elements that spread by horizontal transfer.

  View details for DOI 10.1111/1758-2229.12372

  View details for Web of Science ID 000372931000008

  View details for PubMedID 26711897

  View details for PubMedCentralID PMC4819714

• The cystic fibrosis lower airways microbial metagenome. ERJ open research Moran Losada, P., Chouvarine, P., Dorda, M., Hedtfeld, S., Mielke, S., Schulz, A., Wiehlmann, L., Tümmler, B. 2016; 2 (2)

  Abstract

  Chronic airway infections determine most morbidity in people with cystic fibrosis (CF). Herein, we present unbiased quantitative data about the frequency and abundance of DNA viruses, archaea, bacteria, moulds and fungi in CF lower airways. Induced sputa were collected on several occasions from children, adolescents and adults with CF. Deep sputum metagenome sequencing identified, on average, approximately 10 DNA viruses or fungi and several hundred bacterial taxa. The metagenome of a CF patient was typically found to be made up of an individual signature of multiple, lowly abundant species superimposed by few disease-associated pathogens, such as Pseudomonas aeruginosa and Staphylococcus aureus, as major components. The host-associated signatures ranged from inconspicuous polymicrobial communities in healthy subjects to low-complexity microbiomes dominated by the typical CF pathogens in patients with advanced lung disease. The DNA virus community in CF lungs mainly consisted of phages and occasionally of human pathogens, such as adeno- and herpesviruses. The S. aureus and P. aeruginosa populations were composed of one major and numerous minor clone types. The rare clones constitute a low copy genetic resource that could rapidly expand as a response to habitat alterations, such as antimicrobial chemotherapy or invasion of novel microbes.

  View details for DOI 10.1183/23120541.00096-2015

  View details for PubMedID 27730195

  View details for PubMedCentralID PMC5005179

• Interclonal gradient of virulence in the Pseudomonas aeruginosa pangenome from disease and environment ENVIRONMENTAL MICROBIOLOGY Hilker, R., Munder, A., Klockgether, J., Losada, P., Chouvarine, P., Cramer, N., Davenport, C. F., Dethlefsen, S., Fischer, S., Peng, H., Schoenfelder, T., Tuerk, O., Wiehlmann, L., Woelbeling, F., Gulbins, E., Goesmann, A., Tuemmler, B. 2015; 17 (1): 29–46

  Abstract

  The population genomics of Pseudomonas aeruginosa was analysed by genome sequencing of representative strains of the 15 most frequent clonal complexes in the P. aeruginosa population and of the five most common clones from the environment of which so far no isolate from a human infection has been detected. Gene annotation identified 5892-7187 open reading frame (ORFs; median 6381 ORFs) in the 20 6.4-7.4 Mbp large genomes. The P. aeruginosa pangenome consists of a conserved core of at least 4000 genes, a combinatorial accessory genome of a further 10 000 genes and 30 000 or more rare genes that are present in only a few strains or clonal complexes. Whole genome comparisons of single nucleotide polymorphism synteny indicated unrestricted gene flow between clonal complexes by recombination. Using standardized acute lettuce, Galleria mellonella and murine airway infection models the full spectrum of possible host responses to P. aeruginosa was observed with the 20 strains ranging from unimpaired health following infection to 100% lethality. Genome comparisons indicate that the differential genetic repertoire of clones maintains a habitat-independent gradient of virulence in the P. aeruginosa population.

  View details for DOI 10.1111/1462-2920.12606

  View details for Web of Science ID 000349152800005

  View details for PubMedID 25156090

• THOC5, a member of the mRNA export complex, contributes to processing of a subset of wingless/integrated (Wnt) target mRNAs and integrity of the gut epithelial barrier BMC CELL BIOLOGY Saran, S., Tran, D. H., Klebba-Faerber, S., Moran-Losada, P., Wiehlmann, L., Koch, A., Chopra, H., Pabst, O., Hoffmann, A., Klopfleisch, R., Tamura, T. 2013; 14: 51

  Abstract

  THO (Suppressors of the transcriptional defects of hpr1 delta by overexpression) complex 5 (THOC5), an mRNA export protein, is involved in the expression of only 1% of all genes. Using an interferon inducible knockout mouse system, we have previously shown that THOC5 is an essential element in the maintenance of hematopoietic stem cells and cytokine-mediated hematopoiesis in adult mice. Here we interrogate THOC5 function in cell differentiation beyond the hematopoietic system and study pathological changes caused by THOC5 deficiency.To examine whether THOC5 plays a role in general differentiation processes, we generated tamoxifen inducible THOC5 knockout mice. We show here that the depletion of THOC5 impaired not only hematopoietic differentiation, but also differentiation and self renewal of the gut epithelium. Depletion of the THOC5 gene did not cause pathological alterations in liver or kidney. We further show that THOC5 is indispensable for processing of mRNAs induced by Wnt (wingless/integrated) signaling which play key roles in epithelial cell differentiation/proliferation. A subset of Wnt target mRNAs, SRY-box containing gene 9 (Sox9), and achaete-scute complex homolog 2 (Ascl2), but not Fibronectin 1 (Fn1), were down-regulated in THOC5 knockout intestinal cells. The down-regulated Wnt target mRNAs were able to bind to THOC5. Furthermore, pathological alterations in the gastrointestinal tract induced translocation of intestinal bacteria and caused sepsis in mice. The bacteria translocation may cause Toll-like receptor activation. We identified one of the Toll-like receptor inducible genes, prostaglandin-endoperoxidase synthase 2 (Ptgs2 or COX2) transcript as THOC5 target mRNA.THOC5 is indispensable for processing of only a subset of mRNAs, but plays a key role in processing of mRNAs inducible by Wnt signals. Furthermore, THOC5 is dispensable for general mRNA export in terminally differentiated organs, indicating that multiple mRNA export pathways exist. These data imply that THOC5 may be a useful tool for studying intestinal stem cells, for modifying the differentiation processes and for cancer therapy.

  View details for DOI 10.1186/1471-2121-14-51

  View details for Web of Science ID 000328430500001

  View details for PubMedID 24267292

  View details for PubMedCentralID PMC4222586