Precision dynamical mapping using topological data analysis reveals a hub-like transition state at rest
(2022) Nature Communications, 13 (1), art. no. 4791, .
Saggar, M.a , Shine, J.M.b , Liégeois, R.c d , Dosenbach, N.U.F.e , Fair, D.f
a Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, United States
b Brain and Mind Center, The University of Sydney, Sydney, NSW, Australia
c Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
d Department of Radiology and Medical Informatics, Faculty of Medicine, University of Geneva, Geneva, Switzerland
e Departments of Neurology, Radiology, Pediatrics and Biomedical Engineering, Washington University School of Medicine, St. Louis, MO, United States
f Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN, United States
Abstract
In the absence of external stimuli, neural activity continuously evolves from one configuration to another. Whether these transitions or explorations follow some underlying arrangement or lack a predictable ordered plan remains to be determined. Here, using fMRI data from highly sampled individuals (~5 hours of resting-state data per individual), we aimed to reveal the rules that govern transitions in brain activity at rest. Our Topological Data Analysis based Mapper approach characterized a highly visited transition state of the brain that acts as a switch between different neural configurations to organize the spontaneous brain activity. Further, while the transition state was characterized by a uniform representation of canonical resting-state networks (RSNs), the periphery of the landscape was dominated by a subject-specific combination of RSNs. Altogether, we revealed rules or principles that organize spontaneous brain activity using a precision dynamics approach. © 2022, The Author(s).
Funding details
51NF40_180888, DA041148, MH096773, MH115357
National Institutes of HealthNIHDP2, K99/R00, MH104605, MH119735, NS088590
NIH Blueprint for Neuroscience Research1U54MH091657
McDonnell Center for Systems Neuroscience
Stanford Maternal and Child Health Research InstituteMCHRI
Jacobs Foundation2016121703
Document Type: Article
Publication Stage: Final
Source: Scopus
Longitudinal Changes in Vision and Retinal Morphology in Wolfram Syndrome
(2022) American Journal of Ophthalmology, 243, pp. 10-18.
O’Bryhim, B.E.a , Samara, A.b c , Chen, L.c , Hershey, T.b d e , Tychsen, L.a f , Hoekel, J.a
a John F. Hardesty Department of Ophthalmology and Visual Science, Washington University School of Medicine, and St. Louis Children’s Hospital, St. Louis, Missouri, United States
b Department of Psychiatry, Washington University School of Medicine, and St. Louis Children’s Hospital, St. Louis, Missouri, United States
c Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri, United States
d Department of Neurology, Washington University School of Medicine, and St. Louis Children’s Hospital, St. Louis, Missouri, United States
e Department of Radiology, Washington University School of Medicine, and St. Louis Children’s Hospital, St. Louis, Missouri, United States
f Department of Pediatrics, Washington University School of Medicine, and St. Louis Children’s Hospital, St. Louis, Missouri, United States
Abstract
PURPOSE: To report long-term ophthalmic findings in Wolfram syndrome, including rates of visual decline, macular thinning, retinal nerve fiber layer (RNFL) thinning, and outer plexiform layer (OPL) lamination. DESIGN: Single-center, cohort study. METHODS: A total of 38 participants were studied, who underwent a complete ophthalmic examination as well as optical coherence tomography imaging of the macula and nerve on an annual basis. Linear mixed-effects models for longitudinal data were used to examine both fixed and random effects related to visual acuity and optic nerve quadrants of RNFL and macula thickness. RESULTS: Participants completed a mean of 6.44 years of follow-up (range 2-10 years). Visual acuity declined over time in all participants, with a mean slope of 0.059 logMAR/y (95% CI = 0.07-0.05 logMAR/y), although nearly 25% of participants experienced more rapid visual decline. RNFL thickness decreased in superior, inferior, and nasal quadrants (β = −0.5 µm/y, −0.98 µm/y, −0.28 µm/y, respectively). OPL lamination was noted in 3 study participants, 2 of whom had autosomal dominant mutations. CONCLUSIONS: Our study describes the longest and largest natural history study of visual acuity decline and retinal morphometry in Wolfram syndrome to date. Results suggest that there are slower and faster progressing subgroups and that OPL lamination is present in some individuals with this disease. © 2022 Elsevier Inc.
Funding details
National Institutes of HealthNIH5T32DA007261–29, HD070855, U54 HD087011
American Diabetes AssociationADA
University of WashingtonUWDK020579, UL1 RR024992
McDonnell Center for Systems Neuroscience
Document Type: Article
Publication Stage: Final
Source: Scopus
Amyloid- β and tau deposition influences cognitive and functional decline in Down syndrome
(2022) Neurobiology of Aging, 119, pp. 36-45.
Grigorova, M.a , Mak, E.a , Brown, S.S.G.a , Beresford-Webb, J.a , Hong, Y.T.b , Fryer, T.D.b , Coles, J.P.c , Aigbirhio, F.I.b , Tudorascu, D.d , Cohen, A.d , Christian, B.T.e , Ances, B.f , Handen, B.L.d , Laymon, C.M.g , Klunk, W.E.d , Clare, I.C.H.a , Holland, A.J.a , Zaman, S.H.a
a Cambridge Intellectual and Developmental Disabilities Research Group, Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
b Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
c Department of Medicine, University of Cambridge, Cambridge, United Kingdom
d Department of Psychiatry, University of Pittsburgh, Pittsburgh, United States
e Waisman Brain Imaging Laboratory, University of Wisconsin-Madison, Madison, WI, United States
f Department of Neurology, Washington University at St. Louis, St. Louis, WA, United States
g Department of Radiology and Bioengineering, University of Pittsburgh, Pittsburgh, United States
Abstract
This study investigates whether tau has (i) an independent effect from amyloid-β on changes in cognitive and functional performance and (ii) a synergistic relationship with amyloid-β in the exacerbation of decline in aging Down syndrome (DS). 105 participants with DS underwent baseline PET [18F]-AV1451 and PET [11C]PiB scans to quantify tau deposition in Braak regions II-VI and the Striatum and amyloid-β status respectively. Linear Mixed Effects models were implemented to assess how tau and amyloid-β deposition are related to change over three time points. Tau was a significant independent predictor of cognitive and functional change. The three-way interaction between time, [11C]PiB status and tau was significant in the models of episodic memory and visuospatial cognition. Baseline tau is a significant predictor of cognitive and functional decline, over and above the effect of amyloid-β status. Results suggest a synergistic relationship between amyloid-β status and tau as predictors of change in memory and visuospatial cognition. © 2022 The Authors
Author Keywords
Alzheimer’s disease; Amyloid-β; Down syndrome; PET [11C]PiB; PET [18F]-AV1451; Tau
Funding details
National Institute on AgingNIA
National Institute of Child Health and Human DevelopmentNICHDU01AG051406
Alzheimer’s Society443 JF-18- 017, RG9611
Alzheimer’s Research UKARUKARUK-PG2015-23
NIHR Cambridge Biomedical Research CentreBRC-1215-20014
Document Type: Article
Publication Stage: Final
Source: Scopus
Neurofibromatosis-1 Gene Mutational Profiles Differ Between Syndromic Disease and Sporadic Cancers
(2022) Neurology: Genetics, 8 (4), art. no. e200003, .
Bewley, A.F.a , Akinwe, T.M.b , Turner, T.N.b , Gutmann, D.H.c
a Departments of Medicine, Washington University, St. Louis, MO, United States
b Genetics, Washington University, St. Louis, MO, United States
c Neurology, Washington University, St. Louis, MO, United States
Abstract
ObjectivesVariants in the neurofibromatosis type 1 (NF1) gene are not only responsible for the NF1 cancer predisposition syndrome, but also frequently identified in cancers arising in the general population. While germline variants are pathogenic, it is not known whether those that arise in cancer (somatic variants) are passenger or driver variants. To address this question, we sought to define the landscape of NF1 variants in sporadic cancers.MethodsNF1 variants in sporadic cancers were compiled using data curated on the c-Bio database and compared with published germline variants and Genome Aggregation Database data. Pathogenicity was determined using Polyphen and Sorting Intolerant From Tolerant prediction tools.ResultsThe spectrum of NF1 variants in sporadic tumors differ from those most commonly seen in individuals with NF1. In addition, the type and location of the variants in sporadic cancer differ from germline variants, where a high proportion of missense variants were found. Finally, many of the sporadic cancer NF1 variants were not predicted to be pathogenic.DiscussionTaken together, these findings suggest that a significant proportion of NF1 variants in sporadic cancer may be passenger variants or hypomorphic alleles. Further mechanistic studies are warranted to define their unique roles in nonsyndromic cancer pathobiology. © American Academy of Neurology.
Funding details
National Institutes of HealthNIH1-R35-NS07211-01
Document Type: Article
Publication Stage: Final
Source: Scopus
Cochlear ribbon synapse maturation requires Nlgn1 and Nlgn3
(2022) iScience, 25 (8), art. no. 104803, .
Ramirez, M.A.a , Ninoyu, Y.b , Miller, C.c , Andrade, L.R.c , Edassery, S.a , Bomba-Warczak, E.a , Ortega, B.b , Manor, U.c , Rutherford, M.A.d , Friedman, R.A.b , Savas, J.N.a
a Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
b Division of Otolaryngology, Department of Surgery, University of California, San Diego, 9500 Gilman Drive, Mail Code 0666, La Jolla, CA 92093, United States
c Waitt Advanced Biophotonics Core, Salk Institute for Biological Studies, 10010 N. Torrey Pines Road, La Jolla, CA 92037, United States
d Department of Otolaryngology, Washington University in St. Louis School of Medicine, St. Louis, MO, United States
Abstract
Hearing depends on precise synaptic transmission between cochlear inner hair cells and spiral ganglion neurons through afferent ribbon synapses. Neuroligins (Nlgns) facilitate synapse maturation in the brain, but they have gone unstudied in the cochlea. We report Nlgn3 and Nlgn1 knockout (KO) cochleae have fewer ribbon synapses and have impaired hearing. Nlgn3 KO is more vulnerable to noise trauma with limited activity at high frequencies one day after noise. Furthermore, Nlgn3 KO cochleae have a 5-fold reduction in synapse number compared to wild type after two weeks of recovery. Double KO cochlear phenotypes are more prominent than the KOs, for example, 5-fold smaller synapses, 25% reduction in synapse density, and 30% less synaptic output. These observations indicate Nlgn3 and Nlgn1 are essential to cochlear ribbon synapse maturation and function. © 2022 The Author(s)
Author Keywords
cellular neuroscience; genomics; neuroscience; sensory neuroscience
Funding details
National Science FoundationNSF2014862, R21 DC018237
National Institutes of HealthNIHP30 014195
National Cancer InstituteNCI5R01 DC018566, CCSG P30 CA060553, R00 DC-013805, R01 DC014712, T32 MH067564, W81XWH-19-1-0627
Greenwall FoundationGFM.A.R1, M.A.R2
Northwestern UniversityNU
Australian Biological Resources StudyABRS
Document Type: Article
Publication Stage: Final
Source: Scopus
A central alarm system that gates multi-sensory innate threat cues to the amygdala
(2022) Cell Reports, 40 (7), art. no. 111222, .
Kang, S.J.a , Liu, S.a b , Ye, M.a , Kim, D.-I.a , Pao, G.M.c d , Copits, B.A.e f , Roberts, B.Z.g , Lee, K.-F.a , Bruchas, M.R.h , Han, S.a b g
a Peptide Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, United States
b Department of Neurobiology, School of Biological Sciences, University of California, San Diego, La Jolla, CA 92093, United States
c Molecular and Cellular Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, United States
d Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan
e Washington University Pain Center, Washington University School of Medicine, St. Louis, MO 63110, United States
f Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, United States
g Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, United States
h Center of Excellence in the Neurobiology of Addiction, Pain, and Emotion, Departments of Anesthesiology and Pain Medicine, Pharmacology, University of Washington, Seattle, WA 98195, United States
Abstract
Perception of threats is essential for survival. Previous findings suggest that parallel pathways independently relay innate threat signals from different sensory modalities to multiple brain areas, such as the midbrain and hypothalamus, for immediate avoidance. Yet little is known about whether and how multi-sensory innate threat cues are integrated and conveyed from each sensory modality to the amygdala, a critical brain area for threat perception and learning. Here, we report that neurons expressing calcitonin gene-related peptide (CGRP) in the parvocellular subparafascicular nucleus in the thalamus and external lateral parabrachial nucleus in the brainstem respond to multi-sensory threat cues from various sensory modalities and relay negative valence to the lateral and central amygdala, respectively. Both CGRP populations and their amygdala projections are required for multi-sensory threat perception and aversive memory formation. The identification of unified innate threat pathways may provide insights into developing therapeutic candidates for innate fear-related disorders. © 2022 The Author(s)
Author Keywords
central amygdala; CGRP; CP: Neuroscience; innate threats; lateral amygdala; lateral parabrachial nucleus; multi-sensory; parvocellular subparafascicular nucleus; PBel; SPFp; threat memory
Funding details
1R01MH111520, R01MH112355
National Institute of Mental HealthNIMH
Mary K. Chapman Foundation
Simons Foundation Autism Research InitiativeSFARI388708
Document Type: Article
Publication Stage: Final
Source: Scopus
Dual ontogeny of disease-associated microglia and disease inflammatory macrophages in aging and neurodegeneration
(2022) Immunity, 55 (8), pp. 1448-1465.e6.
Silvin, A.a b , Uderhardt, S.c d e , Piot, C.a , Da Mesquita, S.f g , Yang, K.a , Geirsdottir, L.h , Mulder, K.b , Eyal, D.h , Liu, Z.i , Bridlance, C.j , Thion, M.S.j , Zhang, X.M.a , Kong, W.T.a , Deloger, M.k , Fontes, V.c d e , Weiner, A.h , Ee, R.a , Dress, R.a , Hang, J.W.l , Balachander, A.a , Chakarov, S.a i , Malleret, B.a l , Dunsmore, G.b , Cexus, O.b m , Chen, J.a , Garel, S.j , Dutertre, C.A.a b , Amit, I.h , Kipnis, J.f n , Ginhoux, F.a b i o
a Singapore Immunology Network, Agency for Science, Technology and Research, Singapore, 138648, Singapore
b INSERM U1015, Gustave Roussy Cancer Campus, Villejuif, 94800, France
c Department of Medicine 3 – Rheumatology and Immunology, Friedrich-Alexander-University Erlangen-Nürnberg (FAU) and Universitätsklinikum Erlangen, Erlangen, 91054, Germany
d Deutsches Zentrum für Immuntherapie, FAU, Erlangen, 91054, Germany
e Exploratory Research Unit, Optical Imaging Centre Erlangen, FAU, Erlangen, 91058, Germany
f Department of Neuroscience, Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA 22908, United States
g Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, United States
h Department of Immunology, Weizmann Institute of Science, Rehovot, 76100, Israel
i Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, Shanghai, 200025, China
j Institut de Biologie de l’Ecole Normale Supérieure (IBENS), Ecole Normale Supérieure, CNRS, INSERM, PSL Research University, Paris, 75005, France
k INSERM US23, CNRS UMS 3655, Gustave Roussy Cancer Campus, Villejuif, 94800, France
l Department of Microbiology and Immunology, Immunology Translational Research Programme, Yong Loo Lin School of Medicine, Immunology Programme, Life Sciences Institute, National University of Singapore, Singapore, 117543, Singapore
m School Biosciences and Medicine, Faculty of Health and Medical Sciences, University of Surrey, Guildford, GU2 7XH, United Kingdom
n Center for Brain Immunology and Glia, Department of Pathology and Immunology, School of Medicine, Washington University in St Louis, St Louis, MO 63110, United States
o Translational Immunology Institute, SingHealth Duke-NUS Academic Medical Centre, Singapore, 169856, Singapore
Abstract
Brain macrophage populations include parenchymal microglia, border-associated macrophages, and recruited monocyte-derived cells; together, they control brain development and homeostasis but are also implicated in aging pathogenesis and neurodegeneration. The phenotypes, localization, and functions of each population in different contexts have yet to be resolved. We generated a murine brain myeloid scRNA-seq integration to systematically delineate brain macrophage populations. We show that the previously identified disease-associated microglia (DAM) population detected in murine Alzheimer’s disease models actually comprises two ontogenetically and functionally distinct cell lineages: embryonically derived triggering receptor expressed on myeloid cells 2 (TREM2)-dependent DAM expressing a neuroprotective signature and monocyte-derived TREM2-expressing disease inflammatory macrophages (DIMs) accumulating in the brain during aging. These two distinct populations appear to also be conserved in the human brain. Herein, we generate an ontogeny-resolved model of brain myeloid cell heterogeneity in development, homeostasis, and disease and identify cellular targets for the treatment of neurodegeneration. © 2022 Elsevier Inc.
Author Keywords
aging; Alzheimer’s disease; disease inflammatory macrophages; disease-associated microglia; macrophage; microglia; neurodegeneration
Funding details
European Molecular Biology OrganizationEMBO
European Research CouncilERC101039438
Agency for Science, Technology and ResearchA*STARNRFI2017-02, NUHSRO/2018/006/SU/01
National University of SingaporeNUS
Deutsche ForschungsgemeinschaftDFG405969122, 448121430, 448121523
Biomedical Research CouncilBMRCH16/99/b0/011, IAF311006
Document Type: Article
Publication Stage: Final
Source: Scopus
Development of an acellular nerve cap xenograft for neuroma prevention
(2022) Journal of Biomedical Materials Research – Part A, .
Faust, A.E.a , Soletti, L.a , Cwalina, N.A.a , Miller, A.D.b , Wood, M.D.c , Mahan, M.A.d , Cheetham, J.a e f , Brown, B.N.a f g
a Renerva, LLC, Pittsburgh, PA, United States
b Department of Biomedical Sciences, Section of Anatomic Pathology, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
c Division of Plastic and Reconstructive Surgery, Department of Surgery, Washington University, St. Louis School of Medicine, St. Louis, MO, United States
d Department of Neurosurgery, Clinical Neurosciences Center, University of Utah, Salt Lake City, UT, United States
e Department of Clinical Sciences, Cornell College of Veterinary Medicine, Cornell University, Ithaca, NY, United States
f McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
g Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, United States
Abstract
Neuroma formation following limb amputation is a prevalent and debilitating condition that can deeply affect quality of life and productivity. Several approaches exist to prevent or treat neuromas; however, no approach is either consistently reliable or surgically facile, with high rates of neuroma occurrence and/or recurrence. The present study describes the development and testing of a xenogeneic nerve cap graft made from decellularized porcine nerve. The grafts were tested in vitro for cellular removal, cytotoxicity, mechanical properties, and morphological characteristics. The grafts were then tested in rat sciatic nerve gap reconstruction and nerve amputation models for 8 weeks. Gross morphology, electrophysiology, and histopathology assessments were performed to determine the ability of the grafts to limit pathologic nerve regrowth. In vitro testing showed well decellularized and demyelinated nerve cap graft structures without any cytotoxicity from residual reagents. The grafts had a proximal socket for the proximal nerve stump and longitudinally oriented internal pores. Mechanical and surgical handling properties suggested suitability for implantation as a nerve graft. Following 8 weeks in vivo, the grafts were well integrated with the proximal and distal nerve segments without evidence of fibrotic adhesions to the surrounding tissues or bulbous outgrowth of the nerve. Electrophysiology revealed absence of nerve conduction within the remodeled nerve cap grafts and significant downstream muscle atrophy. Histologic evaluation showed well organized but limited axonal regrowth within the grafts without fibrous overgrowth or neuromatous hypercellularity. These results provide proof of concept for a novel xenograft-based approach to neuroma prevention. © 2022 Wiley Periodicals LLC.
Author Keywords
acellular; extracellular matrix; nerve cap; neuroma; xenograft
Funding details
National Science FoundationNSF1913761
Document Type: Article
Publication Stage: Article in Press
Source: Scopus
To BYOD or not: Are device latencies important for bring-your-own-device (BYOD) smartphone cognitive testing?
(2022) Behavior Research Methods, .
Nicosia, J.a , Wang, B.b , Aschenbrenner, A.J.a , Sliwinski, M.J.c , Yabiku, S.T.d , Roque, N.A.e , Germine, L.T.f g , Bateman, R.J.a , Morris, J.C.a , Hassenstab, J.a h
a Charles F. and Joanne Knight Alzheimer Disease Research Center, Department of Neurology, Washington University School of Medicine, St. Louis, MO, United States
b Mountain View, United States
c Department of Human Development and Family Studies, The Pennsylvania State University, University Park, PA, United States
d Department of Sociology and Criminology, The Pennsylvania State University, University Park, PA, United States
e Department of Psychology, University of Central Florida, Orlando, FL, United States
f Department of Psychiatry, Harvard Medical School, Boston, MA, United States
g Institute for Technology in Psychiatry, McLean Hospital, Belmont, MA, United States
h Department of Psychological & Brain Sciences, Washington University in St. Louis, St. Louis, MO, United States
Abstract
Studies using remote cognitive testing must make a critical decision: whether to allow participants to use their own devices or to provide participants with a study-specific device. Bring-your-own-device (BYOD) studies have several advantages including increased accessibility, potential for larger sample sizes, and reduced participant burden. However, BYOD studies offer little control over device performance characteristics that could potentially influence results. In particular, response times measured by each device not only include the participant’s true response time, but also latencies of the device itself. The present study investigated two prominent sources of device latencies that pose significant risks to data quality: device display output latency and touchscreen input latency. We comprehensively tested 26 popular smartphones ranging in price from < $100 to $1000+ running either Android or iOS to determine if hardware and operating system differences led to appreciable device latency variability. To accomplish this, a custom-built device called the Latency and Timing Assessment Robot (LaTARbot) measured device display output and capacitive touchscreen input latencies. We found considerable variability across smartphones in display and touch latencies which, if unaccounted for, could be misattributed as individual or group differences in response times. Specifically, total device (sum of display and touch) latencies ranged from 35 to 140 ms. We offer recommendations to researchers to increase the precision of data collection and analysis in the context of remote BYOD studies. © 2022, The Psychonomic Society, Inc.
Author Keywords
Ambulatory assessment; BYOD; Remote assessment; Smartphones
Funding details
National Institutes of HealthNIHP01 AG003991, R01 AG057840, U2C AG060408
BrightFocus FoundationBFFA2018202S
Document Type: Article
Publication Stage: Article in Press
Source: Scopus
Reduction of protein disulfide isomerase results in open conformations and stimulates dynamic exchange between structural ensembles
(2022) Journal of Biological Chemistry, 2022, 298(8), 102217
Chinnaraj, M., Flaumenhaft, R., Pozzi, N.
Abstract
Human protein disulfide isomerase (PDI) is an essential redox-regulated enzyme required for oxidative protein folding. It comprises four thioredoxin domains, two catalytically active (a, a’) and two inactive (b, b’), organized to form a flexible abb’a’ U-shape. Snapshots of unbound oxidized and reduced PDI have been obtained by X-ray crystallography. Yet, how PDI’s structure changes in response to the redox environment and inhibitor binding remains controversial. Here, we used multiparameter confocal single-molecule FRET to track the movements of the two catalytic domains with high temporal resolution. We found that at equilibrium, PDI visits three structurally distinct conformational ensembles, two “open” (O1 and O2) and one “closed” (C). We show that the redox environment dictates the time spent in each ensemble and the rate at which they exchange. While oxidized PDI samples O1, O2, and C more evenly and in a slower fashion, reduced PDI predominantly populates O1 and O2 and exchanges between them more rapidly, on the submillisecond timescale. These findings were not expected based on crystallographic data. Using mutational analyses, we further demonstrate that the R300-W396 cation-π interaction and active site cysteines dictate, in unexpected ways, how the catalytic domains relocate. Finally, we show that irreversible inhibitors targeting the active sites of reduced PDI did not abolish these protein dynamics but rather shifted the equilibrium toward the closed ensemble. This work introduces a new structural framework that challenges current views of PDI dynamics, helps rationalize its multifaceted role in biology, and should be considered when designing PDI-targeted therapeutics. © 2022 The Authors
Author keywords
allostery; protein disulfide isomerase; protein dynamics; single-molecule FRET; thiol isomerases; thrombosis