Medical Molecular Biology Commons^™

K-Mer Analysis Of Long-Read Alignment Pileups For Structural Variant Genotyping, Adam C English, Fabio Cunial, Ginger A Metcalf, Richard A Gibbs, Fritz J Sedlazeck

Faculty, Staff and Students Publications

Accurately genotyping structural variant (SV) alleles is crucial to genomics research. We present a novel method (kanpig) for genotyping SVs that leverages variant graphs and k-mer vectors to rapidly generate accurate SV genotypes. Benchmarking against the latest SV datasets shows kanpig achieves a single-sample genotyping concordance of 82.1%, significantly outperforming existing tools, which average 66.3%. We explore kanpig's use for multi-sample projects by testing on 47 genetically diverse samples and find kanpig accurately genotypes complex loci (e.g. SVs neighboring other SVs), and produces higher genotyping concordance than other tools. Kanpig requires only 43 seconds to process a single sample's 20x …

Clinical Validation Of Rna Sequencing For Mendelian Disorder Diagnostics, Sen Zhao, Kristina Macakova, Jefferson C Sinson, Hongzheng Dai, Jill Rosenfeld, Gladys E Zapata, Shenglan Li, Patricia A Ward, Christiana Wang, Chunjing Qu, Becky Maywald, Brendan Lee, Christine Eng, Pengfei Liu

Faculty, Staff and Students Publications

Despite rapid advancements in clinical sequencing, over half of diagnostic evaluations still lack definitive results. RNA sequencing (RNA-seq) has shown promise in research settings for bridging this gap by providing essential functional data for accurate interpretation of diagnostic sequencing results. However, despite advanced research pipelines, clinical translation of diagnostic RNA-seq has not yet been realized. We have developed and validated a clinical diagnostic RNA-seq test for individuals with suspected genetic disorders who have existing or concurrent comprehensive DNA diagnostic testing. This diagnostic RNA-seq test processes RNA samples from fibroblasts or blood and derives clinical interpretations based on the analytical detection …

Bone-Induced Her2 Promotes Secondary Metastasis In Hr+/Her2- Breast Cancer, Rahat Alam, Anna Reva, David G Edwards, Bree M Lege, Laura S Munoz-Arcos, Carolina Reduzzi, Swarnima Singh, Xiaoxin Hao, Yi-Hsuan Wu, Zeru Tian, Laura M Natalee, Gargi Damle, Deniz Demircioglu, Yixian Wang, Ling Wu, Elisabetta Molteni, Dan Hasson, Bora Lim, Zbigniew Gugala, Jerry E Chipuk, Julie E Lang, Joseph A Sparano, Chonghui Cheng, Massimo Cristofanilli, Han Xiao, Xiang H-F Zhang, Igor L Bado

Faculty, Staff and Students Publications

Bone metastases can disseminate to secondary sites and promote breast cancer progression creating additional clinical challenges. The mechanisms contributing to secondary metastasis are barely understood. Here, we evaluate the prediction power of Her2-expressing (Her2E) circulating tumor cells (CTCs) after analyzing over 13,000 CTCs from a cohort of 137 metastatic breast cancer (MBC) patients with initial HR+/Her2− status and employ preclinical models of bone metastasis (BM) to validate the role of Her2E CTCs in multi-organ metastases. While Her2 expression was higher in patients with bone metastasis, experimental analyses revealed that Her2E CTCs derived from bone lesions were more dependent on Her2 …

Rhythm Is Essential: Unraveling The Relation Between The Circadian Clock And Cancer, Olajumoke Ogunlusi, Abantika Ghosh, Mrinmoy Sarkar, Kayla Carter, Harshini Davuluri, Mahul Chakraborty, Kristin Eckel-Mahan, Alex Keene, Jerome S Menet, Deborah Bell-Pedersen, Tapasree Roy Sarkar

The Brown Foundation: Institute of Molecular Medicine

Physiological processes such as the sleep-wake cycle, metabolism, hormone secretion, neurotransmitter release, sensory capabilities, and a variety of behaviors, including sleep, are controlled by a circadian rhythm adapted to 24-hour day-night periodicity. Disruption of circadian rhythm may lead to the risks of numerous diseases, including cancers. Several epidemiological and clinical data reveal a connection between the disruption of circadian rhythms and cancer. On the contrary, oncogenic processes may suppress the homeostatic balance imposed by the circadian clock. The integration of circadian biology into cancer research offers new options for making cancer treatment more effective, and the pharmacological modulation of core …

Epigenome-Wide Association Study Of Incident Type 2 Diabetes In Black And White Participants From The Atherosclerosis Risk In Communities Study, Sowmya Venkataraghavan, James S Pankow, Eric Boerwinkle, Myriam Fornage, Elizabeth Selvin, Debashree Ray

The Brown Foundation: Institute of Molecular Medicine

Aims/hypothesis: DNA methylation studies of incident type 2 diabetes in US populations are limited and to our knowledge none include individuals of African descent. We aimed to fill this gap by identifying methylation sites (CpG sites) and regions likely influencing the development of type 2 diabetes using data from Black and White individuals from the USA.

Methods: We prospectively followed 2091 Black and 1029 White individuals without type 2 diabetes from the Atherosclerosis Risk in Communities study over a median follow-up period of 17 years, and performed an epigenome-wide association analysis of blood-based methylation levels with incident type 2 diabetes …

Calcium-Sensing Receptor As A Novel Target For The Treatment Of Idiopathic Pulmonary Fibrosis, Kasope Wolffs, Renjiao Li, Bethan Mansfield, Daniel A Pass, Richard T Bruce, Ping Huang, Rachel Paes De Araújo, Bahareh Sadat Haddadi, Luis A J Mur, Jordanna Dally, Ryan Moseley, Rupert Ecker, Harry Karmouty-Quintana, Keir E Lewis, A John Simpson, Jeremy P T Ward, Christopher J Corrigan, Renata Z Jurkowska, Benjamin D Hope-Gill, Daniela Riccardi, Polina L Yarova

Faculty, Staff and Student Publications

Idiopathic pulmonary fibrosis (IPF) is a disease with a poor prognosis and no curative therapies. Fibroblast activation by transforming growth factor β1 (TGFβ1) and disrupted metabolic pathways, including the arginine-polyamine pathway, play crucial roles in IPF development. Polyamines are agonists of the calcium/cation-sensing receptor (CaSR), activation of which is detrimental for asthma and pulmonary hypertension, but its role in IPF is unknown. To address this question, we evaluated polyamine abundance using metabolomic analysis of IPF patient saliva. Furthermore, we examined CaSR functional expression in human lung fibroblasts (HLFs), assessed the anti-fibrotic effects of a CaSR antagonist, NPS2143, in TGFβ1-activated normal …

Playbook Workflow Builder: Interactive Construction Of Bioinformatics Workflows, Daniel J B Clarke, John Erol Evangelista, Zhuorui Xie, Giacomo B Marino, Anna I Byrd, Mano R Maurya, Sumana Srinivasan, Keyang Yu, Varduhi Petrosyan, Matthew E Roth, Miroslav Milinkov, Charles Hadley King, Jeet Kiran Vora, Jonathon Keeney, Christopher Nemarich, William Khan, Alexander Lachmann, Nasheath Ahmed, Alexandra Agris, Juncheng Pan, Srinivasan Ramachandran, Eoin Fahy, Emmanuel Esquivel, Aleksandar Mihajlovic, Bosko Jevtic, Vuk Milinovic, Sean Kim, Patrick Mcneely, Tianyi Wang, Eric Wenger, Miguel A Brown, Alexander Sickler, Yuankun Zhu, Sherry L Jenkins, Philip D Blood, Deanne M Taylor, Adam C Resnick, Raja Mazumder, Aleksandar Milosavljevic, Shankar Subramaniam, Avi Ma'ayan

Faculty, Staff and Students Publications

The Playbook Workflow Builder (PWB) is a web-based platform to dynamically construct and execute bioinformatics workflows by utilizing a growing network of input datasets, semantically annotated API endpoints, and data visualization tools contributed by an ecosystem of collaborators. Via a user-friendly user interface, workflows can be constructed from contributed building-blocks without technical expertise. The output of each step of the workflow is added into reports containing textual descriptions, figures, tables, and references. To construct workflows, users can click on cards that represent each step in a workflow, or construct workflows via a chat interface that is assisted by a large …

Warm-Ischemia And Cold Storage Induced Modulation Of Ferroptosis Observed In Human Hearts Donated After Circulatory Death And Brain Death, Shiyi Li, Katherine V Nordick, Abdussalam E Elsenousi, Rishav Bhattacharya, Randall P Kirby, Adel M Hassan, Camila Hochman-Mendez, Todd K Rosengart, Kenneth K Liao, Nandan K Mondal

Faculty, Staff and Students Publications

We investigated ferroptosis, a type of programmed cell death mechanism, in human hearts donated after brain death (DBD) and those donated after circulatory death (DCD), focusing on warm ischemia time (WIT) and cold storage. A total of 24 hearts were procured, with six from the DBD group and 18 from the DCD group. The DCD group was divided into three subgroups, each containing six hearts, based on different WITs of 20, 40, and 60 min. All procured hearts were placed in cold storage for up to 6 h. Left ventricular biopsies were performed at 0, 2, 4, and 6 h. …

Acute Kidney Injury In Severe Alcohol-Associated Hepatitis Treated With Anakinra Plus Zinc Or Prednisone, Kavish R Patidar, Wanzhu Tu, Thomas G Cotter, Douglas A Simonetto, Amon Asgharpour, Muhammad Y Jan, Qing Tang, Yunpeng Yu, Yang Li, Moyinoluwa Taiwo, Prashanth Thevkar Nagesh, Srinivasan Dasarathy, Patrick S Kamath, Craig J Mcclain, Naga Chalasani, Gyongyi Szabo, Ramon Bataller, Mack Mitchell, Wajahat Z Mehal, Laura E Nagy, Vijay H Shah, Samer Gawrieh, Arun J Sanyal

Faculty, Staff and Students Publications

Background and aims: In a recent trial, patients with severe alcohol-associated hepatitis treated with anakinra plus zinc (A+Z) had lower survival and higher acute kidney injury (AKI) rates versus prednisone (PRED). We characterize the clinical factors and potential mechanisms associated with AKI development in that trial.

Approach and results: Data from 147 participants in a multicenter randomized clinical trial (74 A+Z, 73 PRED) were analyzed. AKI, AKI phenotypes, and kidney injury biomarkers were compared between participants who did/did not develop AKI in the 2 treatment arms. Multivariable competing risk analyses were performed to identify baseline risk factors for incident AKI, …

Il-12-Producing Cytokine Factories Induce Precursor Exhausted T Cells And Elimination Of Primary And Metastatic Tumors, Amanda Nash, Jonathon Debonis, Danna Murungi, Bertha Castillo, Boram Kim, Fangheng Hu, Courtney Chambers, Annie Nguyen, Andrea Hernandez, Zeshi Wang, Peter D Rios, Sofia Ghani, Ira Joshi, Douglas Isa, Ningbo Zheng, Weiyi Peng, Oleg A Igoshin, Jose Oberholzer, H Courtney Hodges, Nathan Reticker-Flynn, Omid Veiseh

Faculty, Staff and Students Publications

Background: Curative responses to immunotherapy require the generation of robust systemic immunity with limited toxicity. Recruitment of T cell populations such as precursor exhausted T cells (Tpex) from lymphoid tissues to tumors is a hallmark of effective treatment. However, the ability to efficiently induce this recruitment is lacking in current immunotherapy approaches. Furthermore, systemic administration of immunotherapies frequently results in dose-limiting toxicities, yielding an inadequate therapeutic window for eliciting durable responses.

Methods: In this investigation, we evaluated the safety and antitumor efficacy of locally administered interleukin 12 (IL-12) using a clinically translatable cytokine delivery platform (NCT05538624) to identify …

Outcomes Of Autologous Versus Synthetic Inlay Grafts After Skull Base Reconstruction For High-Flow Defects: A Multicenter Case-Control Analysis, Theodore V Nguyen, Arash Abiri, Victoria Idowu, Saawan Patel, Thomas Truong, David K Lerner, Alan D Workman, Pete S Batra, Raewyn G Campbell, John R Craig, Dana L Crosby, Jennifer E Douglas, Jacob G Eide, Michael A Kohanski, Rijul S Kshirsagar, Tran B Locke, Peter Papagiannopoulos, Bobby A Tajudeen, Charles C L Tong, Nithin D Adappa, James N Palmer, Edward C Kuan

Faculty, Staff and Students Publications

No abstract provided.

Suppression Of Hypothalamic Oestrogenic Signal Sustains Hyperprolactinemia And Metabolic Adaptation In Lactating Mice, Meng Yu, Bing Feng, Jonathan C Bean, Qianru Zhao, Yongjie Yang, Hailan Liu, Yongxiang Li, Benjamin P Eappen, Hesong Liu, Longlong Tu, Kristine M Conde, Mengjie Wang, Xi Chen, Na Yin, Darah Ave Threat, Nathan Xu, Junying Han, Peiyu Gao, Yi Zhu, Darryl L Hadsell, Yang He, Pingwen Xu, Yanlin He, Chunmei Wang

Faculty, Staff and Students Publications

17β-oestradiol (E2) inhibits overeating and promotes brown adipose tissue (BAT) thermogenesis, whereas prolactin (PRL) does the opposite. During lactation, the simultaneous decline in E2 and surge in PRL contribute to maternal metabolic adaptations, including hyperphagia and suppressed BAT thermogenesis. However, the underlying neuroendocrine mechanisms remain unclear. Here, we find that oestrogen receptor alpha (ERα)-expressing neurons in the medial basal hypothalamus (MBH), specifically the arcuate nucleus of the hypothalamus and the ventrolateral subdivision of the ventromedial hypothalamus (vlVMH), are suppressed during lactation. Deletion of ERα from MBH neurons in virgin female mice induces metabolic phenotypes characteristic of lactation, including hyperprolactinemia, hyperphagia …

Single-Nucleus Transcriptional Profiling Of The Placenta Reveals The Syncytiotrophoblast Stress Response To Covid-19, Rachel A Keuls, Scott A Ochsner, Mary B O'Neill, Diana R O'Day, Akihiko Miyauchi, Kadeshia M Campbell, Natalie Lanners, Jeffery A Goldstein, Connor Yee, Neil J Mckenna, Ronald J Parchem, Jacqueline G Parchem

Faculty, Staff and Students Publications

Background: COVID-19 in pregnancy is associated with placental immune activation, inflammation, and vascular malperfusion, but its impact on syncytiotrophoblast biology and function is unclear.

Objective: This study aimed to determine the effects of maternal COVID-19 on placental syncytiotrophoblasts using single-nucleus transcriptional profiling and to compare placental stress responses in COVID-19 and preeclampsia.

Study design: For transcriptional characterization of syncytiotrophoblasts, we used the single-nucleus RNA sequencing platform, single-cell combinatorial indexing RNA sequencing (sci-RNA-seq3), to profile placental villi and fetal membranes from unvaccinated patients with symptomatic COVID-19 at birth (n = 4), gestational age-matched controls (n = 4), and a case of …

Unveiling Racial Disparities In Prostate Cancer Using An Integrative Genomic And Transcriptomic Analysis, Abdalla Elbialy, Akshay Sood, Shang-Jui Wang, Peng Wang, Ahmed Fadiel, Anil V Parwani, Steven Huang, Gennady Shvets, Nagireddy Putluri, Jenny Li, Xuefeng Liu

Faculty, Staff and Students Publications

Prostate cancer exhibits significant racial disparities, with African American (AA) individuals showing ∼64% higher incidence and 2.3 times greater mortality rates compared to their Caucasian (CA) counterparts. Understanding the complex interplay of genetic, environmental, lifestyle, socioeconomic, and healthcare access factors is crucial for developing effective interventions to reduce this disproportionate burden.

This study aims to uncover the genetic and transcriptomic differences driving these disparities through a comprehensive analysis using RNA sequencing (RNA-seq) and exome sequencing of prostate cancer tissues from both Black and White patients.

Our transcriptomics analysis revealed enhanced activity in pathways linked to immune response and cellular interactions …

Clinical And Genetic Delineation Of Autosomal Recessive And Dominant Actl6b-Related Developmental Brain Disorders, Elisa Cali, Tania Quirin, Clarissa Rocca, Stephanie Efthymiou, Antonella Riva, Dana Marafi, Maha S Zaki, Mohnish Suri, Roberto Dominguez, Hasnaa M Elbendary, Shahryar Alavi, Mohamed S Abdel-Hamid, Heba Morsy, Frederic Tran Mau-Them, Mathilde Nizon, Pavel Tesner, Lukáš Ryba, Faisal Zafar, Nuzhat Rana, Nebal W Saadi, Zahra Firoozfar, Pinar Gencpinar, Bulent Unay, Canan Ustun, Ange-Line Bruel, Christine Coubes, Jennifer Stefanich, Ozlem Sezer, Emanuele Agolini, Antonio Novelli, Gessica Vasco, Donatella Lettori, Mathieu Milh, Laurent Villard, Shimriet Zeidler, Henry Opperman, Vincent Strehlow, Mahmoud Y Issa, Hebatallah El Khassab, Prem Chand, Shahnaz Ibrahim, Ali Rashidi-Nezhad, Mohammad Miryounesi, Pegah Larki, Jennifer Morrison, Ingrid Cristian, Isabelle Thiffault, Nicole L Bertsch, Grace J Noh, John Pappas, Ellen Moran, Nikolaos M Marinakis, Joanne Traeger-Synodinos, Susan Hosseini, Mohammad Reza Abbaszadegan, Roseline Caumes, Lisenka E L M Vissers, Maedeh Neshatdoust, Mostafa Montazer Zohour, Elmostafa El Fahime, Christina Canavati, Lara Kamal, Moien Kanaan, Omar Askander, Victoria Voinova, Olga Levchenko, Shahzhad Haider, Sara S Halbach, Rayana Elias Maia, Salehi Mansoor, Vivek Jain, Sanjukta Tawde, Viveka Santhosh R Challa, Vykuntaraju K Gowda, Varunvenkat M Srinivasan, Lucas Alves Victor, Benito Pinero-Banos, Jennifer Hague, Heba Ahmed Elawady, Adelia Maria De Miranda Henriques-Souza, Huma Arshad Cheema, Muhammad Nadeem Anjum, Sara Idkaidak, Firas Alqarajeh, Osama Atawneh, Hagar Mor-Shaked, Tamar Harel, Giovanni Zifarelli, Peter Bauer, Fernando Kok, Joao Paulo Kitajima, Fabiola Monteiro, Juliana Josahkian, Gaetan Lesca, Nicolas Chatron, Dorothe Ville, David Murphy, Jeffrey L Neul, Sureni V Mullegama, Amber Begtrup, Isabella Herman, Tadahiro Mitani, Jennifer E Posey, Chee Geap Tay, Iram Javed, Lucinda Carr, Farah Kanani, Fiona Beecroft, Lee Hane, Elsayed Abdelkreem, Milan Macek, Luciana Bispo, Marwa Abd Elmaksoud, Farzad Hashemi-Gorji, Davut Pehlivan, David J Amor, Rami Abou Jamra, Wendy K Chung, Eshan Ghayoor Karimiani, Philippe M Campeau, Fowzan S Alkuraya, Alistair T Pagnamenta, Joseph G Gleeson, James R Lupski, Pasquale Striano, Andres Moreno-De-Luca, Denis L J Lafontaine, Henry Houlden, Reza Maroofian

Faculty, Staff and Students Publications

Purpose: This study aims to comprehensively delineate the phenotypic spectrum of ACTL6B-related disorders, previously associated with both autosomal recessive and autosomal dominant neurodevelopmental disorders. Molecularly, the role of the nucleolar protein ACTL6B in contributing to the disease has remained unclear.

Methods: We identified 105 affected individuals, including 39 previously reported cases, and systematically analyzed detailed clinical and genetic data for all individuals. Additionally, we conducted knockdown experiments in neuronal cells to investigate the role of ACTL6B in ribosome biogenesis.

Results: Biallelic variants in ACTL6B are associated with severe-to-profound global developmental delay/intellectual disability, infantile intractable seizures, absent speech, autistic features, dystonia, …

Time Tracking And Comparison Of Genetic Counseling Tasks In Inpatient And Outpatient Settings, Alexandra Osborne, Emily Magness Bland, Callie Diamonstein, Kristen Fishler

Faculty, Staff and Students Publications

Genetic counselors (GCs) practice in critical care settings. Some GCs have full-time inpatient roles, while most GCs who see inpatients do so as needed or on a rotating schedule in addition to seeing patients in an outpatient setting. Few studies have tracked and compared the amount of time it takes GCs to perform tasks in the inpatient and outpatient settings. Genetic counselors were invited to participate in this study via the National Society of Genetic Counselors research listserv. Participants completed an online survey asking how their role is structured and what types of support are available to them while seeing …

Limosilactobacillus Reuteri Promotes The Expression And Secretion Of Enteroendocrine- And Enterocyte-Derived Hormones, Sara C Di Rienzi, Heather A Danhof, Micah D Forshee, Ari Roberts, Robert A Britton

Faculty, Staff and Students Publications

Intestinal microbes can beneficially impact host physiology, prompting investigations into the therapeutic usage of such microbes in a range of diseases. For example, human intestinal microbe Limosilactobacillus reuteri strains ATCC PTA 6475 and DSM 17938 are being considered for use for intestinal ailments, including colic, infection, and inflammation, as well as for non-intestinal ailments, including osteoporosis, wound healing, and autism spectrum disorder. While many of their beneficial properties are attributed to suppressing inflammatory responses, we postulated that L. reuteri may also regulate intestinal hormones to affect physiology within and outside of the gut. To determine if L. reuteri secreted factors …

Uterine Pgrmc2 Deficiency Attenuates Endometrial Hyperplasia And Cancer And Prolongs Lifespan In A Pten Loss-Of-Function-Induced Cancer Model, Nicole C Kelp, Cindy A Pru, Sandeep Paudel, John P Lydon, J Julie Kim, John J Peluso, James K Pru

Faculty, Staff and Students Publications

The expression of members of the progesterone receptor membrane component (PGRMC) family, particularly PGRMC1, is elevated in diverse types of cancers, particularly those of the female reproductive system. While xenograft tumor studies using human transformed cell lines in immunocompromised mice have suggested that PGRMC1 enhances tumor growth and chemoresistance, the exact role of members of the PGRMC family in cancer development in vivo remains unclear. In this study, we examined the effect of deleting Pgrmc2 on the development of endometrial hyperplasia and cancer using a murine phosphatase and tensin homologue (Pten) conditional loss-of-function model. We previously established that …

Dock2 Deficiency And Gata2 Haploinsufficiency Can Underlie Critical Coronavirus Disease 2019 (Covid-19) Pneumonia, Sajjad Biglari, Leila Youssefian, Mohammad Amin Tabatabaiefar, Amir Hossein Saeidian, Bahareh Abtahi-Naeini, Erfan Khorram, Roya Sherkat, Atefeh Sohanforooshan Moghaddam, Fatemeh Mohaghegh, Maziyar Rahimi, Hamid Rahimi, Sharareh Babaei, Mohammad Shahrooei, Nikoo Mozafari, Shirin Zaresharifi, Fatemeh Vahidnezhad, Vida Homayouni, Lam C Tsoi, Johann E Gudjonsson, Hakon Hakonarson, Jean-Laurent Casanova, Emmanuelle Jouanguy, Vivien Béziat, Qian Zhang, Aurélie Cobat, Hassan Vahidnezhad

Faculty, Staff and Students Publications

The life-threatening coronavirus disease 2019 (COVID-19) affects about 1 in 1,000 healthy people under 50 without underlying conditions. Among patients with critical COVID-19 pneumonia, rare germline variants at genes controlling type I IFN immunity have been reported in up to 5% of patients. Causal etiologies in 80-85% of cases are still unknown. We analyzed two families with hypoxemic COVID-19 pneumonia for known single-gene inborn errors of immunity. In Family 1, two siblings with critical COVID-19 were homozygous for a DOCK2 variant, c.3624+5G>A. DOCK2 deficiency is a known T-cell disorder underlying severe viral diseases. The variant resulted in skipping exon …

Dependence Of Mitochondrial Calcium Signalling And Dynamics On The Disaggregase, Clpb, Donato D'Angelo, Víctor H. Sánchez-Vázquez, Benjamín Cartes-Saavedra, Denis Vecellio Reane, Ryan R. Cupo, Hilda Delgado De La Herran, Giorgia Ghirardo, James Shorter, Ron A. Wevers, Saskia B. Wortmann, Fabiana Perocchi, Rosario Rizzuto, Anna Raffaello, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Cells utilize protein disaggregases to avoid abnormal protein aggregation that causes many diseases. Among these, caseinolytic peptidase B protein homolog (CLPB) is localized in the mitochondrial intermembrane space and linked to human disease. Upon CLPB loss, MICU1 and MICU2, regulators of the mitochondrial calcium uniporter complex (mtCU), and OPA1, a main mediator of mitochondrial fusion, become insoluble but the functional outcome remains unclear. In this work we demonstrate that CLPB is required to maintain mitochondrial calcium signalling and fusion dynamics. CLPB loss results in altered mtCU composition, interfering with mitochondrial calcium uptake independently of cytosolic calcium and mitochondrial membrane potential. …