Medicine and Health Sciences Commons^™

Structure Of Adenylyl Cyclase 5 In Complex With Gβγ Offers Insights Into Adcy5-Related Dyskinesia, Yu-Chen Yen, Yong Li, Chun-Liang Chen, Thomas Klose, Val J Watts, Carmen W Dessauer, John J G Tesmer

Faculty, Staff and Student Publications

The nine different membrane-anchored adenylyl cyclase isoforms (AC1-9) in mammals are stimulated by the heterotrimeric G protein, Gαs, but their response to Gβγ regulation is isoform specific. In the present study, we report cryo-electron microscope structures of ligand-free AC5 in complex with Gβγ and a dimeric form of AC5 that could be involved in its regulation. Gβγ binds to a coiled-coil domain that links the AC transmembrane region to its catalytic core as well as to a region (C1b) that is known to be a hub for isoform-specific regulation. We confirmed the Gβγ interaction with both purified proteins and cell-based …

A Group 3 Medulloblastoma Stem Cell Program Is Maintained By Otx2-Mediated Alternative Splicing, Olivier Saulnier, Jamie Zagozewski, Lisa Liang, Liam D Hendrikse, Paul Layug, Victor Gordon, Kimberly A Aldinger, Parthiv Haldipur, Stephanie Borlase, Ludivine Coudière-Morrison, Ting Cai, Emma Martell, Naomi M Gonzales, Gareth Palidwor, Christopher J Porter, Stéphane Richard, Tanveer Sharif, Kathleen J Millen, Brad W Doble, Michael D Taylor, Tamra E Werbowetski-Ogilvie

Faculty, Staff and Students Publications

OTX2 is a transcription factor and known driver in medulloblastoma (MB), where it is amplified in a subset of tumours and overexpressed in most cases of group 3 and group 4 MB. Here we demonstrate a noncanonical role for OTX2 in group 3 MB alternative splicing. OTX2 associates with the large assembly of splicing regulators complex through protein-protein interactions and regulates a stem cell splicing program. OTX2 can directly or indirectly bind RNA and this may be partially independent of its DNA regulatory functions. OTX2 controls a pro-tumorigenic splicing program that is mirrored in human cerebellar rhombic lip origins. Among …

Bigh3 Mediates Apoptosis And Gap Junction Failure In Osteocytes During Renal Cell Carcinoma Bone Metastasis Progression, Tianhong Pan, Fengshuo Liu, Xiaoxin Hao, Shubo Wang, Murtaza Wasi, Jian H Song, Valerae O Lewis, Patrick P Lin, Bryan Moon, Justin E Bird, Theocharis Panaretakis, Sue-Hwa Lin, Danielle Wu, Mary C Farach-Carson, Liyun Wang, Ningyan Zhang, Zhiqiang An, Xiang H-F Zhang, Robert L Satcher

Faculty, Staff and Student Publications

Renal cell carcinoma (RCC) bone metastatis progression is driven by crosstalk between tumor cells and the bone microenvironment, which includes osteoblasts, osteoclasts, and osteocytes. RCC bone metastases (RCCBM) are predominantly osteolytic and resistant to antiresorptive therapy. The molecular mechanisms underlying pathologic osteolysis and disruption of bone homeostasis remain incompletely understood. We previously reported that BIGH3/TGFBI (transforming growth factor-beta-induced protein ig-h3, shortened to BIGH3 henceforth) secreted by colonizing RCC cells drives osteolysis by inhibiting osteoblast differentiation, impairing healing of osteolytic lesions, which is reversible with osteoanabolic agents. Here, we report that BIGH3 induces osteocyte apoptosis in both human RCCBM tissue specimens …

Detection Of Soil-Transmitted Helminths And Schistosoma Spp By Nucleic Acid Amplification Test: Results Of The First 5 Years Of The Only International External Quality Assessment Scheme, Annemiek H J Schutte, Rob Koelewijn, Sitara S R Ajjampur, Bruno Levecke, James S Mccarthy, Rojelio Mejia, Steven A Williams, Jaco J Verweij, Lisette Van Lieshout, Jaap J Van Hellemond

Faculty, Staff and Students Publications

BACKGROUND: Infections with soil-transmitted helminths (STH) and schistosomiasis (SCH) result in a significant global health burden, particularly in rural communities in low and middle-income countries. While microscopy remains the primary diagnostic method for STH and SCH in resource-limited settings, nucleic acid amplification tests (NAATs) are gaining prominence as tools for evaluation of public health control programs in endemic countries, and individual diagnosis in high-income countries. Despite the high sensitivity and specificity of NAATs, previous research has highlighted inter-laboratory variations, both in technical and clinical performance, justifying the need for continuous proficiency testing.

METHODOLOGY: Results from 5 rounds over a 5-year …

Circuit-Specific Deep Brain Stimulation Provides Insights Into Movement Control., Aryn H Gittis, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

Deep brain stimulation (DBS), a method in which electrical stimulation is delivered to specific areas of the brain, is an effective treatment for managing symptoms of a number of neurological and neuropsychiatric disorders. Clinical access to neural circuits during DBS provides an opportunity to study the functional link between neural circuits and behavior. This review discusses how the use of DBS in Parkinson's disease and dystonia has provided insights into the brain networks and physiological mechanisms that underlie motor control. In parallel, insights from basic science about how patterns of electrical stimulation impact plasticity and communication within neural circuits are …

Adaptation Of The Protein Misfolding Cyclic Amplification (Pmca) Technique For The Screening Of Anti-Prion Compounds, Katherine Do, Rebeca Benavente, Celso S G Catumbela, Uffaf Khan, Carlos Kramm, Claudio Soto, Rodrigo Morales

Faculty, Staff and Student Publications

Prion diseases result from the misfolding of the physiological prion protein (PrPC) to a pathogenic conformation (PrPSc). Compelling evidence indicates that prevention and/or reduction of PrPSc replication are promising therapeutic strategies against prion diseases. However, the existence of different PrPSc conformations (or strains) associated with disease represents a major problem when identifying anti-prion compounds. Efforts to identify strain-specific anti-prion molecules are limited by the lack of biologically relevant high-throughput screening platforms to interrogate compound libraries. Here, we describe adaptations to the protein misfolding cyclic amplification (PMCA) technology (able to faithfully replicate PrPSc strains) that increase its throughput to facilitate the …

Adhesion G Protein-Coupled Receptor Latrophilin 1 (Adgrl1): A Novel Regulator Of Glucose And Energy Homeostasis., Kavaljit H Chhabra

Pharmacology and Nutritional Sciences Faculty Publications

No abstract provided.

Exploring The Pdz, Duf, And Lim Domains Of Pdlim5 In Dendrite Branching, Yogesh Srivastava, Maxsam Donta, Lydia L Mireles, Adriana Paulucci-Holthauzen, Leilei Shi, Mark T Bedford, M Neal Waxham, Pierre D Mccrea

Faculty, Staff and Student Publications

The branched architecture of neuronal dendrites is a key factor in how neurons form ordered networks and discoveries continue to be made identifying proteins and protein-protein interactions that direct or execute the branching and extension of dendrites. Our prior work showed that the molecular scaffold Pdlim5 and delta-catenin, in conjunction, are two proteins that help regulate the branching and elongation of dendrites in cultured hippocampal neurons and do so through a phosphorylation-dependent mechanism triggered by upstream glutamate signaling. In this report we have focused on Pdlim5's multiple scaffolding domains and how each contributes to dendrite branching. The three identified regions …

Potential Targeting Mechanisms For Bone-Directed Therapies, Betul Celik, Andrés Leal, Shunji Tomatsu

Department of Pediatrics Faculty Papers

Bone development is characterized by complex regulation mechanisms, including signal transduction and transcription factor-related pathways, glycobiological processes, cellular interactions, transportation mechanisms, and, importantly, chemical formation resulting from hydroxyapatite. Any abnormal regulation in the bone development processes causes skeletal system-related problems. To some extent, the avascularity of cartilage and bone makes drug delivery more challenging than that of soft tissues. Recent studies have implemented many novel bone-targeting approaches to overcome drawbacks. However, none of these strategies fully corrects skeletal dysfunction, particularly in growth plate-related ones. Although direct recombinant enzymes (e.g., Vimizim for Morquio, Cerezyme for Gaucher, Elaprase for Hunter, Mepsevii for …

Gabaa Receptor Subunit Composition Regulates Circadian Rhythms In Rest–Wake And Synchrony Among Cells In The Suprachiasmatic Nucleus, Daniel Granados-Fuentes, Peter Lambert, Tatiana Simon, Steven Mennerick, Erik D Herzog

2020-Current year OA Pubs

The mammalian circadian clock located in the suprachiasmatic nucleus (SCN) produces robust daily rhythms including rest-wake. SCN neurons synthesize and respond to γ-aminobutyric acid (GABA), but its role remains unresolved. We tested the hypothesis that γ2- and δ-subunits of the GABA

The Interaction Of Endorepellin And Neurexin Triggers Neuroepithelial Autophagy And Maintains Neural Tube Development, Lei Lu, Meizhu Bai, Yufang Zheng, Xiukun Wang, Zhongzhong Chen, Rui Peng, Richard H Finnell, Tongjin Zhao, Chengtao Li, Bo Wu, Yunping Lei, Jinsong Li, Hongyan Wang

Faculty, Staff and Students Publications

Heparan sulfate proteoglycan 2 (HSPG2) gene encodes the matrix protein Perlecan, and genetic inactivation of this gene creates mice that are embryonic lethal with severe neural tube defects (NTDs). We discovered rare genetic variants of HSPG2 in 10% cases compared to only 4% in controls among a cohort of 369 NTDs. Endorepellin, a peptide cleaved from the domain V of Perlecan, is known to promote angiogenesis and autophagy in endothelial cells. The roles of enderepellin in neurodevelopment remain unclear so far. Our study revealed that endorepellin can migrate to the neuroepithelial cells and then be recognized and bind with the …

The Isr Downstream Target Atf4 Represses Long-Term Memory In A Cell Type-Specific Manner, Niaz Mahmood, Jung-Hyun Choi, Pei You Wu, Sean W Dooling, Trent A Watkins, Ziying Huang, Jesse Lipman, Hanjie Zhao, Anqi Yang, Jake Silversmith, Yanis Inglebert, Constantinos Koumenis, Vijendra Sharma, Jean-Claude Lacaille, Wayne S Sossin, Arkady Khoutorsky, R Anne Mckinney, Mauro Costa-Mattioli, Nahum Sonenberg

Faculty, Staff and Students Publications

The integrated stress response (ISR), a pivotal protein homeostasis network, plays a critical role in the formation of long-term memory (LTM). The precise mechanism by which the ISR controls LTM is not well understood. Here, we report insights into how the ISR modulates the mnemonic process by using targeted deletion of the activating transcription factor 4 (ATF4), a key downstream effector of the ISR, in various neuronal and non-neuronal cell types. We found that the removal of ATF4 from forebrain excitatory neurons (but not from inhibitory neurons, cholinergic neurons, or astrocytes) enhances LTM formation. Furthermore, the deletion of ATF4 in …

The Significant Role Of Amino Acid Metabolic Reprogramming In Cancer, Xiaohong Liu, Bo Ren, Jie Ren, Minzhi Gu, Lei You, Yupei Zhao

Faculty, Staff and Student Publications

Amino acid metabolism plays a pivotal role in tumor microenvironment, influencing various aspects of cancer progression. The metabolic reprogramming of amino acids in tumor cells is intricately linked to protein synthesis, nucleotide synthesis, modulation of signaling pathways, regulation of tumor cell metabolism, maintenance of oxidative stress homeostasis, and epigenetic modifications. Furthermore, the dysregulation of amino acid metabolism also impacts tumor microenvironment and tumor immunity. Amino acids can act as signaling molecules that modulate immune cell function and immune tolerance within the tumor microenvironment, reshaping the anti-tumor immune response and promoting immune evasion by cancer cells. Moreover, amino acid metabolism can …

Cerebellar Nuclei Cells Produce Distinct Pathogenic Spike Signatures In Mouse Models Of Ataxia, Dystonia, And Tremor, Meike E Van Der Heijden, Amanda M Brown, Dominic J Kizek, Roy V Sillitoe

Duncan NRI Faculty and Staff Publications

The cerebellum contributes to a diverse array of motor conditions, including ataxia, dystonia, and tremor. The neural substrates that encode this diversity are unclear. Here, we tested whether the neural spike activity of cerebellar output neurons is distinct between movement disorders with different impairments, generalizable across movement disorders with similar impairments, and capable of causing distinct movement impairments. Using in vivo awake recordings as input data, we trained a supervised classifier model to differentiate the spike parameters between mouse models for ataxia, dystonia, and tremor. The classifier model correctly assigned mouse phenotypes based on single-neuron signatures. Spike signatures were shared …

Targeting Astrogliosis In The Retrotrapezoid Nucleus: A Novel Approach To Ameliorate Respiratory Dysfunction And Alzheimer's Pathology In Mice, Zahid Iqbal, Ahmad El Hamamy, Ngoc Mai Le, Arya Ranjan, Yuxing Zhang, Li Qi, Bharti Manwani, Chunfeng Tan, Louise D Mccullough, Jun Li

Faculty, Staff and Student Publications

Alzheimer's disease (AD), a leading cause of dementia, is associated with significant respiratory dysfunctions. Our study explores the role of astrogliosis in the brainstem retrotrapezoid nucleus (RTN), a key breathing regulatory center, and its impact on breathing control and AD pathology in mice. Using Tg-2576 AD and wild-type mice, we investigated the effect of silencing the transforming growth factor-beta receptor II (TGFβR II) in the RTN. We performed behavioral tests, including the Barnes maze and novel object recognition test, along with whole-body plethysmography to assess breathing disorders. Our results showed that AD mice exhibited increased apneas and cognitive impairment, which …

Macrophage Depletion Protects Against Cisplatin-Induced Ototoxicity And Nephrotoxicity, Cathy Yea Won Sung, Naoki Hayase, Peter S T Yuen, John Lee, Katharine Fernandez, Xuzhen Hu, Hui Cheng, Robert A Star, Mark E Warchol, Lisa L Cunningham

2020-Current year OA Pubs

Cisplatin is a widely used anticancer drug with notable side effects including ototoxicity and nephrotoxicity. Macrophages, the major resident immune cells in the cochlea and kidney, are important drivers of both inflammatory and tissue repair responses. To investigate the roles of macrophages in cisplatin-induced toxicities, we used PLX3397, a U.S. Food and Drug Administration-approved inhibitor of the colony-stimulating factor 1 receptor, to eliminate tissue-resident macrophages. Mice treated with cisplatin alone had considerable hearing loss (ototoxicity) and kidney injury (nephrotoxicity). Macrophage ablation resulted in significantly reduced hearing loss and had greater outer hair cell survival. Macrophage ablation also protected against cisplatin-induced …

N-Myc And Stat Interactor Is An Endometriosis Suppressor, Yuri Park, Xiaoming Guan, Sang Jun Han

Faculty, Staff and Students Publications

In patients with endometriosis, refluxed endometrial fragments evade host immunosurveillance, developing into endometriotic lesions. However, the mechanisms underlying this evasion have not been fully elucidated. N-Myc and STAT Interactor (NMI) have been identified as key players in host immunosurveillance, including interferon (IFN)-induced cell death signaling pathways. NMI levels are markedly reduced in the stromal cells of human endometriotic lesions due to modulation by the Estrogen Receptor beta/Histone Deacetylase 8 axis. Knocking down NMI in immortalized human endometrial stromal cells (IHESCs) led to elevated RNA levels of genes involved in cell-to-cell adhesion and extracellular matrix signaling following IFNA treatment. Furthermore, NMI …

Tert Activation Targets Dna Methylation And Multiple Aging Hallmarks, Hong Seok Shim, Jonathan Iaconelli, Xiaoying Shang, Jiexi Li, Zheng D Lan, Shan Jiang, Kayla Nutsch, Brittney A Beyer, Luke L Lairson, Adam T Boutin, Michael J Bollong, Peter G Schultz, Ronald A Depinho

Faculty, Staff and Student Publications

Insufficient telomerase activity, stemming from low telomerase reverse transcriptase (TERT) gene transcription, contributes to telomere dysfunction and aging pathologies. Besides its traditional function in telomere synthesis, TERT acts as a transcriptional co-regulator of genes pivotal in aging and age-associated diseases. Here, we report the identification of a TERT activator compound (TAC) that upregulates TERT transcription via the MEK/ERK/AP-1 cascade. In primary human cells and naturally aged mice, TAC-induced elevation of TERT levels promotes telomere synthesis, blunts tissue aging hallmarks with reduced cellular senescence and inflammatory cytokines, and silences p16INK4a expression via upregulation of DNMT3B-mediated promoter hypermethylation. In the brain, …

A Correctable Immune Niche For Epithelial Stem Cell Reprogramming And Post-Viral Lung Diseases, Kangyun Wu, Yong Zhang, Huiqing Yin-Declue, Kelly Sun, Dailing Mao, Kuangying Yang, Stephen R. Austin, Erika C. Crouch, Steven L. Brody, Derek E. Byers, Christy M. Hoffmann, Michael E. Hughes, Michael J. Holtzman

2020-Current year OA Pubs

Epithelial barriers are programmed for defense and repair but are also the site of long-term structural remodeling and disease. In general, this paradigm features epithelial stem cells (ESCs) that are called on to regenerate damaged tissues but can also be reprogrammed for detrimental remodeling. Here we identified a Wfdc21-dependent monocyte-derived dendritic cell (moDC) population that functioned as an early sentinel niche for basal ESC reprogramming in mouse models of epithelial injury after respiratory viral infection. Niche function depended on moDC delivery of ligand GPNMB to the basal ESC receptor CD44 so that properly timed antibody blockade of ligand or receptor …

Vaccine Value Profile For Hookworm, Karl Philipp Puchner, Maria Elena Bottazzi, Victoria Periago, Martin Grobusch, Rick Maizels, James Mccarthy, Bruce Lee, Erika Gaspari, David Diemert, Peter Hotez

Faculty, Staff and Students Publications

Hookworm, a parasitic infection, retains a considerable burden of disease, affecting the most underprivileged segments of the general population in endemic countries and remains one of the leading causes of mild to severe anemia in Low and Middle Income Countries (LMICs), particularly in pregnancy and children under 5. Despite repeated large scale Preventive Chemotherapy (PC) interventions since more than 3 decades, there is broad consensus among scholars that elimination targets set in the newly launched NTD roadmap will require additional tools and interventions. Development of a vaccine could constitute a promising expansion of the existing arsenal against hookworm. Therefore, we …

Differential Impact Of Serotonin Signaling Methylphenidate On Young Versus Adult: Insights From Behavioral And Dorsal Raphe Nucleus Neuronal Recordings From Freely Behaving Rats, Nachum Dafny, Gloria M Elizondo, Cruz Perez-Vasquez

Faculty, Staff and Student Publications

Methylphenidate (MPD) remains a cornerstone pharmacological intervention for managing ADHD, yet its increasing usage among ordinary youth and adults outside clinical contexts necessitates a thorough investigation into its developmental effects. This study seeks to simultaneously investigate the behavioral and neuronal changes within the dorsal raphe (DR) nucleus, a center of serotonergic neurons in the mammalian brain, before and after the administration of varying doses of acute and chronic MPD in freely behaving young and adult rats implanted with DR recording electrodes. Wireless neuronal and behavioral recording systems were used over 10 consecutive experimental days. Eight groups were examined: saline, 0.6, …

Pannexin-1 Channel Inhibition Alleviates Opioid Withdrawal In Rodents By Modulating Locus Coeruleus To Spinal Cord Circuitry, Charlie H T Kwok, Tamara Markovic, Nicolas Massaly, Hye Jean Yoon, Jose A Morón, Et Al.

2020-Current year OA Pubs

Opioid withdrawal is a liability of chronic opioid use and misuse, impacting people who use prescription or illicit opioids. Hyperactive autonomic output underlies many of the aversive withdrawal symptoms that make it difficult to discontinue chronic opioid use. The locus coeruleus (LC) is an important autonomic centre within the brain with a poorly defined role in opioid withdrawal. We show here that pannexin-1 (Panx1) channels expressed on microglia critically modulate LC activity during opioid withdrawal. Within the LC, we found that spinally projecting tyrosine hydroxylase (TH)-positive neurons (LC

A Light-Responsive Neural Circuit Suppresses Feeding, Hailan Liu, Na Qu, Natalia Valdez Gonzalez, Marco A Palma, Huamin Chen, Jiani Xiong, Abhinav Choubey, Yongxiang Li, Xin Li, Meng Yu, Hesong Liu, Longlong Tu, Nan Zhang, Na Yin, Kristine Marie Conde, Mengjie Wang, Jonathan Carter Bean, Junying Han, Nikolas Anthony Scarcelli, Yongjie Yang, Kenji Saito, Huxing Cui, Qingchun Tong, Zheng Sun, Chunmei Wang, Xing Cai, Li Lu, Yang He, Yong Xu

Faculty, Staff and Students Publications

Light plays an essential role in a variety of physiological processes, including vision, mood, and glucose homeostasis. However, the intricate relationship between light and an animal's feeding behavior has remained elusive. Here, we found that light exposure suppresses food intake, whereas darkness amplifies it in male mice. Interestingly, this phenomenon extends its reach to diurnal male Nile grass rats and healthy humans. We further show that lateral habenula (LHb) neurons in mice respond to light exposure, which in turn activates 5-HT neurons in the dorsal Raphe nucleus (DRN). Activation of the LHb→5-HTDRN circuit in mice blunts darkness-induced hyperphagia, while inhibition …

Antibody-Activation Of Connexin Hemichannels In Bone Osteocytes With Atp Release Suppresses Breast Cancer And Osteosarcoma Malignancy, Manuel A Riquelme, Xuewei Wang, Francisca M Acosta, Jingruo Zhang, Jeffery Chavez, Sumin Gu, Peng Zhao, Wei Xiong, Ningyan Zhang, Guo Li, Saranya Srinivasan, Chaoyu Ma, Manjeet K Rao, Lu-Zhe Sun, Nu Zhang, Zhiqiang An, Jean X Jiang

The Brown Foundation: Institute of Molecular Medicine

Bone tissue represents the most frequent site of cancer metastasis. We developed a hemichannel-activating antibody, Cx43-M2. Cx43-M2, directly targeting osteocytes in situ, activates osteocytic hemichannels and elevates extracellular ATP, thereby inhibiting the growth and migration of cultured breast and osteosarcoma cancer cells. Cx43-M2 significantly decreases breast cancer metastasis, osteosarcoma growth, and osteolytic activity, while improving survival rates in mice. The antibody's inhibition of breast cancer and osteosarcoma is dose dependent in both mouse and human cancer metastatic models. Furthermore, Cx43-M2 enhances anti-tumor immunity by increasing the population and activation of tumor-infiltrating immune-promoting effector T lymphocytes, while reducing immune-suppressive regulatory T …

Multi-Antigen Intranasal Vaccine Protects Against Challenge With Sarbecoviruses And Prevents Transmission In Hamsters, Ankita Leekha, Arash Saeedi, K M Samiur Rahman Sefat, Monish Kumar, Melisa Martinez-Paniagua, Adrian Damian, Rohan Kulkarni, Kate Reichel, Ali Rezvan, Shalaleh Masoumi, Xinli Liu, Laurence J N Cooper, Manu Sebastian, Courtney M Sands, Vallabh E Das, Nimesh B Patel, Brett Hurst, Navin Varadarajan

Faculty, Staff and Student Publications

Immunization programs against SARS-CoV-2 with commercial intramuscular vaccines prevent disease but are less efficient in preventing infections. Mucosal vaccines can provide improved protection against transmission, ideally for different variants of concern (VOCs) and related sarbecoviruses. Here, we report a multi-antigen, intranasal vaccine, NanoSTING-SN (NanoSTING-Spike-Nucleocapsid), eliminates virus replication in both the lungs and the nostrils upon challenge with the pathogenic SARS-CoV-2 Delta VOC. We further demonstrate that NanoSTING-SN prevents transmission of the SARS-CoV-2 Omicron VOC (BA.5) to vaccine-naïve hamsters. To evaluate protection against other sarbecoviruses, we immunized mice with NanoSTING-SN. We showed that immunization affords protection against SARS-CoV, leading to protection …

Cell-Specific Regulation Of The Circadian Clock By Bmal1 In The Paraventricular Nucleus: Implications For Regulation Of Systemic Biological Rhythms, Rachel Van Drunen, Yulin Dai, Haichao Wei, Baharan Fekry, Sina Noori, Samay Shivshankar, Rafael Bravo, Zhongming Zhao, Seung-Hee Yoo, Nicholas Justice, Jia Qian Wu, Qingchun Tong, Kristin Eckel-Mahan

Faculty, Staff and Student Publications

Circadian rhythms are internal biological rhythms driving temporal tissue-specific, metabolic programs. Loss of the circadian transcription factor BMAL1 in the paraventricular nucleus (PVN) of the hypothalamus reveals its importance in metabolic rhythms, but its functions in individual PVN cells are poorly understood. Here, loss of BMAL1 in the PVN results in arrhythmicity of processes controlling energy balance and alters peripheral diurnal gene expression. BMAL1 chromatin immunoprecipitation sequencing (ChIP-seq) and single-nucleus RNA sequencing (snRNA-seq) reveal its temporal regulation of target genes, including oxytocin (OXT), and restoring circulating OXT peaks in BMAL1-PVN knockout (KO) mice rescues absent activity rhythms. While glutamatergic neurons …

Dna Fork Remodeling Proteins, Zranb3 And Smarcal1, Are Uniquely Essential For Aging Hematopoiesis, Saul Kushinsky, Matthew V. Puccetti, Clare M. Adams, Irina Shkundina, Nikkole James, Brittany M. Mahon, Peter Michener, Christine M. Eischen

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

Over a lifetime, hematopoietic stem and progenitor cells (HSPCs) are forced to repeatedly proliferate to maintain hematopoiesis, increasing their susceptibility to DNA damaging replication stress. However, the proteins that mitigate this stress, protect HSPC replication, and prevent aging-driven dysregulation are unknown. We report two evolutionarily conserved, ubiquitously expressed chromatin remodeling enzymes with similar DNA replication fork reversal biochemical functions, Zranb3 and Smarcal1, have surprisingly specialized roles in distinct HSPC populations. While both proteins actively mitigate replication stress and prevent DNA damage and breaks during lifelong hematopoiesis, the loss of either resulted in distinct biochemical and biological consequences. Notably, defective long-term …

Lipid-Associated Macrophages Reshape Bat Cell Identity In Obesity, Francesca Sciarretta, Wentong Jia, Jonathan R Brestoff, Et Al.

2020-Current year OA Pubs

Obesity and type 2 diabetes cause a loss in brown adipose tissue (BAT) activity, but the molecular mechanisms that drive BAT cell remodeling remain largely unexplored. Using a multilayered approach, we comprehensively mapped a reorganization in BAT cells. We uncovered a subset of macrophages as lipid-associated macrophages (LAMs), which were massively increased in genetic and dietary model of BAT expansion. LAMs participate in this scenario by capturing extracellular vesicles carrying damaged lipids and mitochondria released from metabolically stressed brown adipocytes. CD36 scavenger receptor drove LAM phenotype, and CD36-deficient LAMs were able to increase brown fat genes in adipocytes. LAMs released …

Hyaluronan Mediates Cold-Induced Adipose Tissue Beiging, Xi Chen, Yifan Wang, Huiqiao Li, Yanru Deng, Charlise Giang, Anying Song, Yu'e Liu, Qiong A Wang, Yi Zhu

Faculty, Staff and Students Publications

Adipose tissue beiging refers to the process by which beige adipocytes emerge in classical white adipose tissue depots. Beige adipocytes dissipate chemical energy and secrete adipokines, such as classical brown adipocytes, to improve systemic metabolism, which is beneficial for people with obesity and metabolic diseases. Cold exposure and β3-adrenergic receptor (AR) agonist treatment are two commonly used stimuli for increasing beige adipocytes in mice; however, their underlying biological processes are different. Transcriptional analysis of inguinal white adipose tissue (iWAT) has revealed that changes in extracellular matrix (ECM) pathway genes are specific to cold exposure. Hyaluronic acid (HA), a non-sulfated linear …

Targeted Degradation Of Extracellular Mitochondrial Aspartyl-Trna Synthetase Modulates Immune Responses, Benjamin S Johnson, Janet S Lee, Et Al.

2020-Current year OA Pubs

The severity of bacterial pneumonia can be worsened by impaired innate immunity resulting in ineffective pathogen clearance. We describe a mitochondrial protein, aspartyl-tRNA synthetase (DARS2), which is released in circulation during bacterial pneumonia in humans and displays intrinsic innate immune properties and cellular repair properties. DARS2 interacts with a bacterial-induced ubiquitin E3 ligase subunit, FBXO24, which targets the synthetase for ubiquitylation and degradation, a process that is inhibited by DARS2 acetylation. During experimental pneumonia, Fbxo24 knockout mice exhibit elevated DARS2 levels with an increase in pulmonary cellular and cytokine levels. In silico modeling identified an FBXO24 inhibitory compound with immunostimulatory …