Medical Specialties Commons^™

A Dual Role Of Cohesin In Dna Dsb Repair, Michael Fedkenheuer, Yafang Shang, Seolkyoung Jung, Kevin Fedkenheuer, Solji Park, Davide Mazza, Robin Sebastian, Hiroyuki Nagashima, Dali Zong, Hua Tan, Sushil Kumar Jaiswal, Haiqing Fu, Anthony Cruz, Supriya V Vartak, Jan Wisniewski, Vittorio Sartorelli, John J O'Shea, Laura Elnitski, Andre Nussenzweig, Mirit I Aladjem, Fei-Long Meng, Rafael Casellas

Faculty, Staff and Student Publications

Cells undergo tens of thousands of DNA-damaging events each day. Defects in repairing double-stranded breaks (DSBs) can lead to genomic instability, contributing to cancer, genetic disorders, immunological diseases, and developmental defects. Cohesin, a multi-subunit protein complex, plays a crucial role in both chromosome organization and DNA repair by creating architectural loops through chromatin extrusion. However, the mechanisms by which cohesin regulates these distinct processes are not fully understood. In this study, we identify two separate roles for cohesin in DNA repair within mammalian cells. First, cohesin serves as an intrinsic architectural factor that normally prevents interactions between damaged chromatin. Second, …

Feasibility Of Ex Vivo Ligandomics, Prabuddha Waduge, Remya Ammassam Veettil, Bojun Zhang, Chengchi Huang, Hong Tian, Wei Li

Faculty, Staff and Students Publications

We developed ligandomics for the in vivo profiling of vascular ligands in mice, discovering secretogranin III (Scg3) as a novel angiogenic factor that selectively binds to retinal vessels of diabetic but not healthy mice. This discovery led to the development of anti-Scg3 therapy for ocular vasculopathies. However, in vivo ligandomics requires intracardial perfusion to remove unbound phage clones, limiting its use to vascular endothelial cells (ECs). To extend ligandomics to non-vascular cells, we investigated ex vivo ligandomics. We isolated ECs and retinal ganglion cells (RGCs) from diabetic and healthy mouse retinas by immunopanning. We quantified the binding of clonal phages …

Viroporin Activity Is Necessary For Intercellular Calcium Signals That Contribute To Viral Pathogenesis, J Thomas Gebert, Francesca J Scribano, Kristen A Engevik, Ethan M Huleatt, Michael R Eledge, Lauren E Dorn, Asha A Philip, Takahiro Kawagishi, Harry B Greenberg, John T Patton, Joseph M Hyser

Faculty, Staff and Students Publications

Viruses engage in a variety of processes to subvert host defenses and create an environment amenable to replication. Here, using rotavirus as a prototype, we show that calcium conductance out of the endoplasmic reticulum by the virus encoded ion channel, NSP4, induces intercellular calcium waves that extend beyond the infected cell and contribute to pathogenesis. Viruses that lack the ability to induce this signaling show diminished viral shedding and attenuated disease in a mouse model of rotavirus diarrhea. This implicates nonstructural protein 4 (NSP4) as a virulence factor and provides mechanistic insight into its mode of action. Critically, this …

Nkapl Facilitates Transcription Pause-Release And Bridges Elongation To Initiation During Meiosis Exit, Zhenlong Kang, Chen Xu, Shuai Lu, Jie Gong, Ruoyu Yan, Gan Luo, Yuanyuan Wang, Qing He, Yifei Wu, Yitong Yan, Baomei Qian, Shenglin Han, Zhiwen Bu, Jinwen Zhang, Xian Xia, Liang Chen, Zhibin Hu, Mingyan Lin, Zheng Sun, Yayun Gu, Lan Ye

Faculty, Staff and Students Publications

Transcription elongation, especially RNA polymerase II (Pol II) pause-release, is less studied than transcription initiation in regulating gene expression during meiosis. It is also unclear how transcription elongation interplays with transcription initiation. Here, we show that depletion of NKAPL, a testis-specific protein distantly related to RNA splicing factors, causes male infertility in mice by blocking the meiotic exit and downregulating haploid genes. NKAPL binds to promoter-associated nascent transcripts and co-localizes with DNA-RNA hybrid R-loop structures at GAA-rich loci to enhance R-loop formation and facilitate Pol II pause-release. NKAPL depletion prolongs Pol II pauses and stalls the SOX30/HDAC3 transcription initiation complex …

Utilizing Patient-Derived Xenografts To Model Precision Oncology For Biliary Tract Cancer, Timothy P Diperi, Kurt W Evans, Stephen Scott, Xiaofeng Zheng, Kaushik Varadarajan, Lawrence N Kwong, Michael Kahle, Hop S Tran Cao, Ching-Wei Tzeng, Thuy Vu, Sunhee Kim, Fei Su, Maria Gabriela Raso, Yasmeen Rizvi, Ming Zhao, Huamin Wang, Sunyoung S Lee, Timothy A Yap, Jordi Rodon, Milind Javle, Funda Meric-Bernstam

Faculty, Staff and Student Publications

Purpose: Biliary tract cancers, which are rare and aggressive malignancies, are rich in clinically actionable molecular alterations. A major challenge in the field is the paucity of clinically relevant biliary tract cancer models that recapitulate the diverse molecular profiles of these tumors. The purpose of this study was to curate a collection of patient-derived xenograft (PDX) models that reflect the spectrum of genomic alterations present in biliary tract cancers to create a resource for modeling precision oncology.

Experimental design: PDXs were derived from biliary tract cancer samples collected from surgical resections or metastatic biopsies. Alterations present in the PDXs were …

Targeting Trpc Channels For Control Of Arthritis-Induced Bone Erosion, Suravi Ray, Jamie L Mccall, Jin Bin Tian, Jaepyo Jeon, Aidan Douglas, Kendall Tyler, Siyao Liu, Kendyl Berry, Brady Nicewarner, Casey Hall, Klaus Groschner, Bernadett Bacsa, Werner Geldenhuys, Michael X Zhu, Harry C Blair, John B Barnett, Jonathan Soboloff

Faculty, Staff and Student Publications

Arthritis leads to bone erosion due to an imbalance between osteoclast and osteoblast function. Our prior investigations revealed that the Ca2+-selective ion channel, Orai1, is critical for osteoclast maturation. Here, we show that the small-molecule ELP-004 preferentially inhibits transient receptor potential canonical (TRPC) channels. While ELP-004 minimally affected physiological RANKL-induced osteoclast maturation in murine bone marrow- and spleen-derived myeloid cells (BMSMCs) and human PBMC-derived cells, it potently interfered with osteoclast maturation driven by TNFα or LTB4. The contribution of TRPC channels to osteoclastogenesis was examined using BMSMCs derived from TRPC4-/- or TRPC(1-7)-/- mice, again revealing preferential interference with osteoclastogenesis driven …

Sex Differences In Response To Diet Enriched With Glutathione Precursors In The Aging Heart, Aude Angelini, Grecia Garcia Marquez, Anna Malovannaya, Marta L Fiorotto, Alexander Saltzman, Antrix Jain, Joann Trial, George E Taffet, Katarzyna A Cieslik

Faculty, Staff and Students Publications

Common features of the aging heart are dysregulated metabolism, inflammation, and fibrosis. Elevated oxidative stress is another hallmark of cardiac aging that can exacerbate each of these conditions. We hypothesize that by increasing natural antioxidant levels (glutathione), we will improve cardiac function. Twenty-one-month-old mice were fed glycine and N-acetyl cysteine (GlyNAC; glutathione precursors)-supplemented or control diets for 12 weeks. Heart function was monitored longitudinally, and the exercise performance was determined at the end of the study. We found that the GlyNAC diet was beneficial for old male but not old female mice, leading to an increase of Ndufb8 expression (a …

Foxr2 Targets Lhx6+/Dlx+ Neural Lineages To Drive Central Nervous System Neuroblastoma, Selin Jessa, Antonella De Cola, Bhavyaa Chandarana, Michael Mcnicholas, Steven Hébert, Adam Ptack, Damien Faury, Jessica W Tsai, Andrey Korshunov, Timothy N Phoenix, Benjamin Ellezam, David T W Jones, Michael D Taylor, Pratiti Bandopadhayay, Manav Pathania, Nada Jabado, Claudia L Kleinman

Faculty, Staff and Students Publications

Central nervous system neuroblastoma with forkhead box R2 (FOXR2) activation (NB-FOXR2) is a high-grade tumor of the brain hemispheres and a newly identified molecular entity. Tumors express dual neuronal and glial markers, leading to frequent misdiagnoses, and limited information exists on the role of FOXR2 in their genesis. To identify their cellular origins, we profiled the transcriptomes of NB-FOXR2 tumors at the bulk and single-cell levels and integrated these profiles with large single-cell references of the normal brain. NB-FOXR2 tumors mapped to LHX6+/DLX+ lineages derived from the medial ganglionic eminence, a progenitor domain in the ventral telencephalon. In vivo prenatal …

Electrostatic Force-Enabled Microneedle Patches That Exploit Photoredox Catalysis For Transdermal Phototherapy, Hang Zhang, Wen-Chuan Xie, Yuhang Yao, Zi-Yi Tang, Wen-Xiu Ni, Bingwu Wang, Song Gao, Jonathan L Sessler, Jun-Long Zhang

Faculty, Staff and Student Publications

Microneedle patches for topical administration of photodynamic therapy (PDT) sensitizers are attractive owing to their safety, selectivity, and noninvasiveness. However, low-efficiency photosensitizer delivery coupled with the limitations of the hypoxic tumor microenvironment remains challenging. To overcome these issues, we developed an effective microneedle patch based on intermolecular electrostatic interactions within a photosensitizer matrix containing a zinc-containing porphyrin analogue, ZnBP (w). This design improved the mechanical strength of the microneedle patch and enhanced the photosensitizer loading efficiency in aqueous environments. A key feature of the system is efficient electron transfer between ZnBP (w) and NADH upon photoirradiation. Electrostatic interactions between ZnBP …

A Case For Broadening Our View Of Mechanism In Developmental Biology, B Duygu Özpolat, Swathi Arur, Mansi Srivastava

Faculty, Staff and Student Publications

Developmental biologists can perform studies that describe a phenomenon (descriptive work) and/or explain how the phenomenon works (mechanistic work). There is a prevalent perception that molecular/genetic explanations achieved via perturbations of gene function are the primary means of advancing mechanistic knowledge. We believe this to be a limited perspective, one that does not effectively represent the breadth of work in our field. We surveyed a representative and diverse group of colleagues to share their views on what it takes to infer mechanism. Here, we briefly examine the factors that have shaped the dominant view of mechanism, summarize responses to the …

Anti-Ctla-4 Generates Greater Memory Response Than Anti-Pd-1 Via Tcf-1, Stephen Mok, Huey Liu, Didem Ağaç Çobanoğlu, Nana-Ama A S Anang, James J Mancuso, E John Wherry, James P Allison

Faculty, Staff and Student Publications

The effects of T cell differentiation arising from immune checkpoint inhibition targeting cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1) on the immunological memory response remain unclear. Our investigation into the effects of anti-CTLA-4 and anti-PD-1 on memory T cell formation in mice reveals that memory T cells generated by anti-CTLA-4 exhibit greater expansion, cytokine production, and antitumor activity than those from anti-PD-1. Notably, anti-CTLA-4 preserves more T cell factor-1 (TCF-1)+ T cells during priming, while anti-PD-1 leads to more thymocyte selection-associated high mobility group box (TOX)+ T cells. Experiments using conditional

Infiltrating Plasma Cells Maintain Glioblastoma Stem Cells Through Igg-Tumor Binding, Jiancheng Gao, Danling Gu, Kailin Yang, Junxia Zhang, Qiankun Lin, Wei Yuan, Xu Zhu, Deobrat Dixit, Ryan C Gimple, Hao You, Qian Zhang, Zhumei Shi, Xiao Fan, Qiulian Wu, Chenfei Lu, Zhangchun Cheng, Daqi Li, Linjie Zhao, Bin Xue, Zhu Zhu, Zhe Zhu, Hui Yang, Ningwei Zhao, Wei Gao, Yingmei Lu, Junfei Shao, Chuandong Cheng, Dapeng Hao, Shuo Yang, Yun Chen, Xiaoming Wang, Chunsheng Kang, Jing Ji, Jianghong Man, Sameer Agnihotri, Qianghu Wang, Fan Lin, Xu Qian, Stephen C Mack, Zhibin Hu, Chaojun Li, Michael D Taylor, Yan Li, Nu Zhang, Jeremy N Rich, Yongping You, Xiuxing Wang

Faculty, Staff and Students Publications

Glioblastoma is a highly aggressive primary brain tumor with glioblastoma stem cells (GSCs) enforcing the intra-tumoral hierarchy. Plasma cells (PCs) are critical effectors of the B-lineage immune system, but their roles in glioblastoma remain largely unexplored. Here, we leverage single-cell RNA and B cell receptor sequencing of tumor-infiltrating B-lineage cells and reveal that PCs are aberrantly enriched in the glioblastoma-infiltrating B-lineage population, experience low level of somatic hypermutation, and are associated with poor prognosis. PCs secrete immunoglobulin G (IgG), which stimulates GSC proliferation via the IgG-FcγRIIA-AKT-mTOR axis. Disruption of IgG-FcγRIIA paracrine communication inhibits GSC proliferation and self-renewal. Glioblastoma-infiltrating PCs are …

Lipid Nanoparticles Deliver Dna-Encoded Biologics And Induce Potent Protective Immunity, Dafei Chai, Junhao Wang, Jing Ming Lim, Xiaohui Xie, Xinfang Yu, Dan Zhao, Perry Ayn Mayson Maza, Yifei Wang, Dana Cyril-Remirez, Ken H Young, Yong Li

Faculty, Staff and Students Publications

Lipid nanoparticles (LNPs) for mRNA delivery have advanced significantly, but LNP-mediated DNA delivery still faces clinical challenges. This study compared various LNP formulations for delivering DNA-encoded biologics, assessing their expression efficacy and the protective immunity generated by LNP-encapsulated DNA in different models. The LNP formulation used in Moderna's Spikevax mRNA vaccine (LNP-M) demonstrated a stable nanoparticle structure, high expression efficiency, and low toxicity. Notably, a DNA vaccine encoding the spike protein, delivered via LNP-M, induced stronger antigen-specific antibody and T cell immune responses compared to electroporation. Single-cell RNA sequencing (scRNA-seq) analysis revealed that the LNP-M/pSpike vaccine enhanced CD80 activation signaling …

Identification And Characterization Of A Novel Pavlovskyella (Acari: Argasidae) From Chile, Parasite Of The Culpeo Fox (Lycalopex Culpaeus), Sebastián Muñoz-Leal, Alexander R Kneubehl, Karen Ardiles, Catalina Parragué-Migone, Ignacio Troncoso-Toro, Pablo Oyarzún-Ruiz, Job E Lopez

Faculty, Staff and Students Publications

Soft ticks (Argasidae) of the subgenus Pavlovskyella Pospelova-Shtrom are worldwide distributed parasites of medical importance. However, the systematics of the subgenus are currently under debate because genetic data shows that the group is paraphyletic. Meanwhile, species of Pavlovskyella continue to be discovered. In this study a novel species of the subgenus is described from specimens collected on a fox in central Chile. The larva of this new species differentiates from other Pavlovskyella spp. by having the following combination of characters: subpyriform dorsal plate; 15 pairs of setae, 7 anterolateral, 3 central, and 5 posterolateral, and hypostome with denticles in the …

Zongertinib (Bi 1810631), An Irreversible Her2 Tki, Spares Egfr Signaling And Improves Therapeutic Response In Preclinical Models And Patients With Her2-Driven Cancers, Birgit Wilding, Lydia Woelflingseder, Anke Baum, Krzysztof Chylinski, Gintautas Vainorius, Neil Gibson, Irene C Waizenegger, Daniel Gerlach, Martin Augsten, Fiona Spreitzer, Yukina Shirai, Masachika Ikegami, Sylvia Tilandyová, Dirk Scharn, Mark A Pearson, Johannes Popow, Anna C Obenauf, Noboru Yamamoto, Shunsuke Kondo, Frans L Opdam, Annemarie Bruining, Shinji Kohsaka, Norbert Kraut, John V Heymach, Flavio Solca, Ralph A Neumüller

Faculty, Staff and Student Publications

Mutations in ERBB2 (encoding HER2) occur in 2% to 4% of non-small cell lung cancer (NSCLC) and confer poor prognosis. ERBB-targeting tyrosine kinase inhibitors, approved for treating other HER2-dependent cancers, are ineffective in HER2-mutant NSCLC due to dose-limiting toxicities or suboptimal potency. We report the discovery of zongertinib (BI 1810631), a covalent HER2 inhibitor. Zongertinib potently and selectively blocks HER2, while sparing EGFR, and inhibits the growth of cells dependent on HER2 oncogenic driver events, including HER2-dependent human cancer cells resistant to trastuzumab deruxtecan. Zongertinib displays potent antitumor activity in HER2-dependent human NSCLC xenograft models and enhances the activities of …

Neutrophil Extracellular Traps Promote Pre-Metastatic Niche Formation In The Omentum By Expanding Innate-Like B Cells That Express Il-10, Wonjae Lee, Song Yi Ko, Hironari Akasaka, Melanie Weigert, Ernst Lengyel, Honami Naora

Faculty, Staff and Student Publications

Disseminated cancer cells in the peritoneal fluid often colonize omental fat-associated lymphoid clusters but the mechanisms are unclear. Here, we identify that innate-like B cells accumulate in the omentum of mice and women with early-stage ovarian cancer concomitantly with the extrusion of chromatin fibers by neutrophils called neutrophil extracellular traps (NETs). Studies using genetically modified NET-deficient mice, pharmacologic inhibition of NETs, and adoptive B cell transfer show that NETs induce expression of the chemoattractant CXCL13 in the pre-metastatic omentum, stimulating recruitment of peritoneal innate-like B cells that in turn promote expansion of regulatory T cells and omental metastasis through producing …

Nerves At Play: The Peripheral Nervous System In Extracranial Malignancies, Paola D Vermeer, Anthony C Restaino, Jeffrey L Barr, Dan Yaniv, Moran Amit

Faculty, Staff and Student Publications

The exponential growth of the cancer neuroscience field has shown that the host's immune, vascular, and nervous systems communicate with and influence each other in the tumor microenvironment, dictating the cancer malignant phenotype. Unraveling the nervous system's contributions toward this phenotype brings us closer to cancer cures. In this review, we summarize the peripheral nervous system's contributions to cancer. We highlight the effects of nerve recruitment and tumor innervation, the neuro-immune axis, glial cell activity, and neural regulation on cancer development and progression. We also discuss harnessing the neural control of peripheral cancers as a potential therapeutic approach in oncology. …

Combined Kras Inhibition And Immune Therapy Generates Durable Complete Responses In An Autochthonous Pdac Model, Yonghong Liu, Jincheng Han, Wen-Hao Hsu, Kyle A Labella, Pingna Deng, Xiaoying Shang, Paulino Tallón De Lara, Li Cai, Shan Jiang, Ronald A Depinho

Faculty, Staff and Student Publications

Pancreatic ductal adenocarcinoma (PDAC) resists conventional chemo/radiation and immunotherapy. In PDAC, oncogenic KRAS (KRAS*) drives glycolysis in cancer cells to consume available glucose and produce abundant lactate, creating profound immune suppression in the tumor microenvironment. Here, we combined KRAS* inhibition with agents targeting the major arms of the immunity cycle: CXCR1/2 inhibitor for myeloid cells, antagonistic anti-LAG3 antibody for T cells, and agonistic anti-41BB antibody for dendritic cells. This combination elicited robust anti-tumor regression in iKPC mice bearing large autochthonous tumors. While untreated mice succumbed within 3 weeks, sustained treatment led to durable complete tumor regression and prolonged survival in …

Is Modulation Of Immune Checkpoints On Glioblastoma-Infiltrating Myeloid Cells A Viable Therapeutic Strategy?, Ruochen Du, Jianzhong Zhang, Rimas V Lukas, Shashwat Tripathi, Jared T Ahrendsen, Michael A Curran, Crismita Dmello, Peng Zhang, Roger Stupp, Ganesh Rao, Amy B Heimberger

Faculty, Staff and Students Publications

The field of immunology has traditionally focused on immune checkpoint modulation of adaptive immune cells. However, many malignancies such as glioblastoma are mostly devoid of T cells and rather are enriched with immunosuppressive myeloid cells of the innate immune system. While some immune checkpoint targets are shared between adaptive and innate immunity, myeloid-specific checkpoints could also serve as potential therapeutics. To better understand the impact of immune checkpoint blockade on myeloid cells, we systematically summarize the current literature focusing on the direct immunological effects of PD-L1/PD-1, CD24/Siglec-10, collagen/LAIR-1, CX3CL1/CX3CR1, and CXCL10/CXCR3. By synthesizing the molecular mechanisms and the translational implications, …

Superstable Lipid Vacuoles Endow Cartilage With Its Shape And Biomechanics, Raul Ramos, Kim T Pham, Richard C Prince, Leith B Leiser-Miller, Maneeshi S Prasad, Xiaojie Wang, Rachel C Nordberg, Benjamin J Bielajew, Jerry C Hu, Kosuke Yamaga, Ji Won Oh, Tao Peng, Rupsa Datta, Aksana Astrowskaja, Axel A Almet, John T Burns, Yuchen Liu, Christian Fernando Guerrero-Juarez, Bryant Q Tran, Yi-Lin Chu, Anh M Nguyen, Tsai-Ching Hsi, Norman T-L Lim, Sandra Schoeniger, Ruiqi Liu, Yun-Ling Pai, Chella K Vadivel, Sandy Ingleby, Andrew E Mckechnie, Frank Van Breukelen, Kyle L Hoehn, John J Rasweiler, Michinori Kohara, William J Loughry, Scott H Weldy, Raymond Cosper, Chao-Chun Yang, Sung-Jan Lin, Kimberly L Cooper, Sharlene E Santana, Jeffrey E Bradley, Michael A Kiebish, Michelle Digman, David E James, Amy E Merrill, Qing Nie, Thomas F Schilling, Aliaksandr A Astrowski, Eric O Potma, Martín I García-Castro, Kyriacos A Athanasiou, Richard R Behringer, Maksim V Plikus

Faculty, Staff and Student Publications

Conventionally, the size, shape, and biomechanics of cartilages are determined by their voluminous extracellular matrix. By contrast, we found that multiple murine cartilages consist of lipid-filled cells called lipochondrocytes. Despite resembling adipocytes, lipochondrocytes were molecularly distinct and produced lipids exclusively through de novo lipogenesis. Consequently, lipochondrocytes grew uniform lipid droplets that resisted systemic lipid surges and did not enlarge upon obesity. Lipochondrocytes also lacked lipid mobilization factors, which enabled exceptional vacuole stability and protected cartilage from shrinking upon starvation. Lipid droplets modulated lipocartilage biomechanics by decreasing the tissue's stiffness, strength, and resilience. Lipochondrocytes were found in multiple mammals, including humans, …

Perinuclear Organelle Trauma At The Nexus Of Cardiomyopathy Pathogenesis Arising From Loss Of Function Lmna Mutation, Jason C. Choi

Center for Translational Medicine Faculty Papers

Over the past 25 years, nuclear envelope (NE) perturbations have been reported in various experimental models with mutations in the LMNA gene. Although the hypothesis that NE perturbations from LMNA mutations are a fundamental feature of striated muscle damage has garnered wide acceptance, the molecular sequalae provoked by the NE damage and how they underlie disease pathogenesis such as cardiomyopathy (LMNA cardiomyopathy) remain poorly understood. We recently shed light on one such consequence, by employing a cardiomyocyte-specific Lmna deletion in vivo in the adult heart. We observed extensive NE perturbations prior to cardiac function deterioration with collateral damage in the …

Tamm-Horsfall Protein Augments Neutrophil Netosis During Urinary Tract Infection, Vicki Mercado-Evans, Holly Branthoover, Claude Chew, Camille Serchejian, Alexander B Saltzman, Marlyd E Mejia, Jacob J Zulk, Ingrid Cornax, Victor Nizet, Kathryn A Patras

Faculty, Staff and Students Publications

Urinary neutrophils are a hallmark of urinary tract infection (UTI), yet the mechanisms governing their activation, function, and efficacy in controlling infection remain incompletely understood. Tamm-Horsfall glycoprotein (THP), the most abundant protein in urine, uses terminal sialic acids to bind an inhibitory receptor and dampen neutrophil inflammatory responses. We hypothesized that neutrophil modulation is an integral part of THP-mediated host protection. In a UTI model, THP-deficient mice showed elevated urinary tract bacterial burdens, increased neutrophil recruitment, and more severe tissue histopathological changes compared with WT mice. Furthermore, THP-deficient mice displayed impaired urinary NETosis during UTI. To investigate the effect of …

A Β-Hydroxybutyrate Shunt Pathway Generates Anti-Obesity Ketone Metabolites, Maria Dolores Moya-Garzon, Mengjie Wang, Veronica L Li, Xuchao Lyu, Wei Wei, Alan Sheng-Hwa Tung, Steffen H Raun, Meng Zhao, Laetitia Coassolo, Hashim Islam, Barbara Oliveira, Yuqin Dai, Jan Spaas, Antonio Delgado-Gonzalez, Kenyi Donoso, Aurora Alvarez-Buylla, Francisco Franco-Montalban, Anudari Letian, Catherine P Ward, Lichao Liu, Katrin J Svensson, Emily L Goldberg, Christopher D Gardner, Jonathan P Little, Steven M Banik, Yong Xu, Jonathan Z Long

Children’s Nutrition Research Center Staff Publications

β-Hydroxybutyrate (BHB) is an abundant ketone body. To date, all known pathways of BHB metabolism involve the interconversion of BHB and primary energy intermediates. Here, we identify a previously undescribed BHB secondary metabolic pathway via CNDP2-dependent enzymatic conjugation of BHB and free amino acids. This BHB shunt pathway generates a family of anti-obesity ketone metabolites, the BHB-amino acids. Genetic ablation of CNDP2 in mice eliminates tissue amino acid BHB-ylation activity and reduces BHB-amino acid levels. The most abundant BHB-amino acid, BHB-Phe, is a ketosis-inducible congener of Lac-Phe that activates hypothalamic and brainstem neurons and suppresses feeding. Conversely, CNDP2-KO mice exhibit …

Molecular Logic For Cellular Specializations That Initiate The Auditory Parallel Processing Pathways, Junzhan Jing, Ming Hu, Tenzin Ngodup, Qianqian Ma, Shu-Ning Natalie Lau, M Cecilia Ljungberg, Matthew J Mcginley, Laurence O Trussell, Xiaolong Jiang

Faculty, Staff and Students Publications

The cochlear nuclear complex (CN), the starting point for all central auditory processing, encompasses a suite of neuronal cell types highly specialized for neural coding of acoustic signals. However, the molecular logic governing these specializations remains unknown. By combining single-nucleus RNA sequencing and Patch-seq analysis, we reveal a set of transcriptionally distinct cell populations encompassing all previously observed types and discover multiple hitherto unknown subtypes with anatomical and physiological identity. The resulting comprehensive cell-type taxonomy reconciles anatomical position, morphological, physiological, and molecular criteria, enabling the determination of the molecular basis of the specialized cellular phenotypes in the CN. In particular, …

Functional Characterization Of Qt Interval Associated Scn5a Enhancer Variants Identify Combined Additive Effects, Lavanya Gunamalai, Parul Singh, Brian Berg, Leilei Shi, Ernesto Sanchez, Alexa Smith, Ghislain Breton, Mark T Bedford, Darius Balciunas, Ashish Kapoor

Faculty, Staff and Student Publications

Several empirical and theoretical studies suggest the presence of multiple enhancers per gene that collectively regulate gene expression, and that common sequence variation impacting on the activities of these enhancers is a major source of inter-individual gene expression variability. However, for the vast majority of genes, enhancers and the underlying regulatory variation remains unknown. Even for the genes with well-characterized enhancers, the nature of the combined effects from multiple enhancers and their variants, when known, on gene expression regulation remains unexplored. Here, we have evaluated the combined effects from five SCN5A enhancers and their regulatory variants that are known to …

Alleviation Of Liver Fibrosis By Inhibiting A Non-Canonical Atf4-Regulated Enhancer Program In Hepatic Stellate Cells, Li-Xian Yang, Chuangye Qi, Si Lu, Xiang-Shi Ye, Parnaz Merikhian, Du-Yu Zhang, Tao Yao, Jiang-Sha Zhao, Ying Wu, Yongshi Jia, Bo Shan, Jinghai Chen, Xiaozhou Mou, Jia You, Wenbo Li, Yu-Xiong Feng

Faculty, Staff and Student Publications

Liver fibrosis is a critical liver disease that can progress to more severe manifestations, such as cirrhosis, yet no effective targeted therapies are available. Here, we identify that ATF4, a master transcription factor in ER stress response, promotes liver fibrosis by facilitating a stress response-independent epigenetic program in hepatic stellate cells (HSCs). Unlike its canonical role in regulating UPR genes during ER stress, ATF4 activates epithelial-mesenchymal transition (EMT) gene transcription under fibrogenic conditions. HSC-specific depletion of ATF4 suppresses liver fibrosis in vivo. Mechanistically, TGFβ resets ATF4 to orchestrate a unique enhancer program for the transcriptional activation of pro-fibrotic EMT genes. …

Advancing De Novo Lipogenesis: Genetic And Metabolic Insights, Sean M Hartig, Mark A Herman

Faculty, Staff and Students Publications

De novo lipogenesis (DNL) is the process whereby cells synthesize fatty acids from acetyl-CoA, contributing to steatosis in fatty liver disease. Two new studies, using genetic mouse models, metabolomics, and pharmacology, identified alternative pathways in DNL and unexpected physiological effects when targeting key enzymes in this pathway.

Yap Overcomes Mechanical Barriers To Induce Mitotic Rounding And Adult Cardiomyocyte Division, Yuka Morikawa, Jong H Kim, Rich Gang Li, Lin Liu, Shijie Liu, Vaibhav Deshmukh, Matthew C Hill, James F Martin

Faculty, Staff and Students Publications

Background: Many specialized cells in adult organs acquire a state of cell cycle arrest and quiescence through unknown mechanisms. Our limited understanding of mammalian cell cycle arrest is derived primarily from cell culture models. Adult mammalian cardiomyocytes, a classic example of cell cycle arrested cells, exit the cell cycle postnatally and remain in an arrested state for the life of the organism. Cardiomyocytes can be induced to re-enter the cell cycle by YAP5SA, an active form of the Hippo signaling pathway effector YAP.

Methods: We performed clonal analyses to determine the cell cycle kinetics of YAP5SA cardiomyocytes. We also performed …

Microtubules Sequester Acetylated Yap In The Cytoplasm And Inhibit Heart Regeneration, Shijie Liu, Vaibhav Deshmukh, Fansen Meng, Yidan Wang, Yuka Morikawa, Jeffrey D Steimle, Rich Gang Li, Jun Wang, James F Martin

Faculty, Staff and Students Publications

Background: The Hippo pathway effector YAP (Yes-associated protein) plays an essential role in cardiomyocyte proliferation and heart regeneration. In response to physiological changes, YAP moves in and out of the nucleus. The pathophysiological mechanisms regulating YAP subcellular localization after myocardial infarction remain poorly defined.

Methods: We identified YAP acetylation at site K265 by in vitro acetylation followed by mass spectrometry analysis. We used adeno-associated virus to express YAP-containing mutations that either abolished acetylation (YAP-K265R) or mimicked acetylation (YAP-K265Q) and studied how acetylation regulates YAP subcellular localization in mouse hearts. We generated a cell line with YAP-K265R mutation and investigated the …

Genetics And Biology Of Pancreatic Ductal Adenocarcinoma, Haoqiang Ying, Alec C Kimmelman, Nabeel Bardeesy, Raghu Kalluri, Anirban Maitra, Ronald A Depinho

Faculty, Staff and Student Publications

Pancreatic ductal adenocarcinoma (PDAC) poses a grim prognosis for patients. Recent multidisciplinary research efforts have provided critical insights into its genetics and tumor biology, creating the foundation for rational development of targeted and immune therapies. Here, we review the PDAC genomic landscape and the role of specific oncogenic events in tumor initiation and progression, as well as their contributions to shaping its tumor biology. We further summarize and synthesize breakthroughs in single-cell and metabolic profiling technologies that have illuminated the complex cellular composition and heterotypic interactions of the PDAC tumor microenvironment, with an emphasis on metabolic cross-talk across cancer and …