Digital Commons Network^™

Repair Of Noise-Induced Damage To Stereocilia F-Actin Cores Is Facilitated By Xirp2 And Its Novel Mechanosensor Domain, Elizabeth L Wagner, Jun-Sub Im, Stefano Sala, Maura I Nakahata, Terence E Imbery, Sihan Li, Daniel Chen, Katherine Nimchuk, Yael Noy, David W Archer, Wenhao Xu, George Hashisaki, Karen B Avraham, Patrick W Oakes, Jung-Bum Shin

Faculty, Staff and Student Publications

Prolonged exposure to loud noise has been shown to affect inner ear sensory hair cells in a variety of deleterious manners, including damaging the stereocilia core. The damaged sites can be visualized as 'gaps' in phalloidin staining of F-actin, and the enrichment of monomeric actin at these sites, along with an actin nucleator and crosslinker, suggests that localized remodeling occurs to repair the broken filaments. Herein, we show that gaps in mouse auditory hair cells are largely repaired within 1 week of traumatic noise exposure through the incorporation of newly synthesized actin. We provide evidence that Xin actin binding repeat …

Histone H2a Lys130 Acetylation Epigenetically Regulates Androgen Production In Prostate Cancer, Thanh Nguyen, Dhivya Sridaran, Surbhi Chouhan, Cody Weimholt, Audrey Wilson, Jingqin Luo, Tiandao Li, John Koomen, Bin Fang, Nagireddy Putluri, Arun Sreekumar, Felix Y Feng, Kiran Mahajan, Nupam P Mahajan

Faculty, Staff and Students Publications

The testicular androgen biosynthesis is well understood, however, how cancer cells gauge dwindling androgen to dexterously initiate its de novo synthesis remained elusive. We uncover dual-phosphorylated form of sterol regulatory element-binding protein 1 (SREBF1), pY673/951-SREBF1 that acts as an androgen sensor, and dissociates from androgen receptor (AR) in androgen deficient environment, followed by nuclear translocation. SREBF1 recruits KAT2A/GCN5 to deposit epigenetic marks, histone H2A Lys130-acetylation (H2A-K130ac) in SREBF1, reigniting de novo lipogenesis & steroidogenesis. Androgen prevents SREBF1 nuclear translocation, promoting T cell exhaustion. Nuclear SREBF1 and H2A-K130ac levels are significantly increased and directly correlated with late-stage prostate cancer, reversal of …

Preparation And Immunofluorescence Staining Of Bundles And Single Fiber Cells From The Cortex And Nucleus Of The Eye Lens, Michael P Vu, Catherine Cheng

Faculty, Staff and Student Publications

The lens is a transparent and ellipsoid organ in the anterior chamber of the eye that changes shape to finely focus light onto the retina to form a clear image. The bulk of this tissue comprises specialized, differentiated fiber cells that have a hexagonal cross section and extend from the anterior to the posterior poles of the lens. These long and skinny cells are tightly opposed to neighboring cells and have complex interdigitations along the length of the cell. The specialized interlocking structures are required for normal biomechanical properties of the lens and have been extensively described using electron microscopy …

A Novel Bioactive Peptide, T14, Selectively Activates Mtorc1 Signalling: Therapeutic Implications For Neurodegeneration And Other Rapamycin-Sensitive Applications, Sanskar Ranglani, Anna Ashton, Kashif Mahfooz, Joanna Komorowska, Alexandru Graur, Nadine Kabbani, Sara Garcia-Rates, Susan Greenfield

Faculty, Staff and Student Publications

T14 modulates calcium influx via the α-7 nicotinic acetylcholine receptor to regulate cell growth. Inappropriate triggering of this process has been implicated in Alzheimer's disease (AD) and cancer, whereas T14 blockade has proven therapeutic potential in in vitro, ex vivo and in vivo models of these pathologies. Mammalian target of rapamycin complex 1 (mTORC1) is critical for growth, however its hyperactivation is implicated in AD and cancer. T14 is a product of the longer 30mer-T30. Recent work shows that T30 drives neurite growth in the human SH-SY5Y cell line via the mTOR pathway. Here, we demonstrate that T30 induces an …

Microcalcification Crystallography As A Potential Marker Of Dcis Recurrence, Sarah B Gosling, Emily L Arnold, Samantha K Davies, Hannah Cross, Ihssane Bouybayoune, Doriana Calabrese, Jayakrupakar Nallala, Sarah E Pinder, Liping Fu, Esther H Lips, Lorraine King, Jeffrey Marks, Allison Hall, Lars J Grimm, Thomas Lynch, Donna Pinto, Hilary Stobart, E Shelley Hwang, Jelle Wesseling, Kalotina Geraki, Nicholas Stone, Iain D Lyburn, Charlene Greenwood, Keith D Rogers, Grand Challenge Precision Consortium

Faculty, Staff and Student Publications

Ductal carcinoma in-situ (DCIS) accounts for 20-25% of all new breast cancer diagnoses. DCIS has an uncertain risk of progression to invasive breast cancer and a lack of predictive biomarkers may result in relatively high levels (~ 75%) of overtreatment. To identify unique prognostic biomarkers of invasive progression, crystallographic and chemical features of DCIS microcalcifications have been explored. Samples from patients with at least 5-years of follow up and no known recurrence (174 calcifications in 67 patients) or ipsilateral invasive breast cancer recurrence (179 microcalcifications in 57 patients) were studied. Significant differences were noted between the two groups including whitlockite …

Chronic Basal Forebrain Activation Improves Spatial Memory, Boosts Neurotrophin Receptor Expression, And Lowers Bace1 And Aβ42 Levels In The Cerebral Cortex In Mice, Jacob Kumro, Ashutosh Tripathi, Yun Lei, Jeremy Sword, Patrick Callahan, Alvin Terry, Xin-Yun Lu, Sergei A Kirov, Anilkumar Pillai, David T Blake

Faculty, Staff and Student Publications

The etiology of Alzheimer’s dementia has been hypothesized in terms of basal forebrain cholinergic decline, and in terms of reflecting beta-amyloid neuropathology. To study these different biological elements, we activated the basal forebrain in 5xFAD Alzheimer’s model mice and littermates. Mice received 5 months of 1 h per day intermittent stimulation of the basal forebrain, which includes cholinergic projections to the cortical mantle. Then, mice were behaviorally tested followed by tissue analysis. The 5xFAD mice performed worse in water-maze testing than littermates. Stimulated groups learned the water maze better than unstimulated groups. Stimulated groups had 2–3-fold increases in frontal cortex …

Early Postpartum Hba1c After Hyperglycemia First Detected In Pregnancy-Imperfect But Not Without Value, Ankia Coetzee, David R Hall, Mari Van De Vyver, Magda Conradie

Faculty, Staff and Student Publications

BACKGROUND: South African women of childbearing age are disproportionally affected by obesity and at significant risk of Type 2 Diabetes Mellitus (T2DM). Unless pregnant, they do not readily undergo screening for T2DM. With a local focus on improved antenatal care, hyperglycemia is often first detected in pregnancy (HFDP). This may erroneously be attributed to Gestational Diabetes Mellitus (GDM) in all without considering T2DM. Glucose evaluation following pregnancy is essential for early detection and management of women with T2DM in whom persistent hyperglycemia is to be expected. Conventional testing with an oral glucose tolerance test (OGTT) is cumbersome, prompting investigation for …

Identification Of Key Elements In Prostate Cancer For Ontology Building Via A Multidisciplinary Consensus Agreement, Amy Moreno, Abhishek A Solanki, Tianlin Xu, Ruitao Lin, Jatinder Palta, Emily Daugherty, David Hong, Julian Hong, Sophia C Kamran, Evangelia Katsoulakis, Kristy Brock, Mary Feng, Clifton Fuller, Charles Mayo

Faculty, Staff and Student Publications

BACKGROUND: Clinical data collection related to prostate cancer (PCa) care is often unstructured or heterogeneous among providers, resulting in a high risk for ambiguity in its meaning when sharing or analyzing data. Ontologies, which are shareable formal (i.e., computable) representations of knowledge, can address these challenges by enabling machine-readable semantic interoperability. The purpose of this study was to identify PCa-specific key data elements (KDEs) for standardization in clinic and research.

METHODS: A modified Delphi method using iterative online surveys was performed to report a consensus agreement on KDEs by a multidisciplinary panel of 39 PCa specialists. Data elements were divided …

Targeting Neddylation And Sumoylation In Chemoresistant Triple Negative Breast Cancer, Wei Ruan, Jiwen Li, Seungwon Choi, Xinxin Ma, Yafen Liang, Ragini Nair, Xiaoyi Yuan, Tingting W Mills, Holger K Eltzschig

Faculty, Staff and Student Publications

Previous studies implicate extracellular adenosine signaling in attenuating myocardial ischemia and reperfusion injury (IRI). This extracellular adenosine signaling is terminated by its uptake into cells by equilibrative nucleoside transporters (ENTs). Thus, we hypothesized that targeting ENTs would function to increase cardiac adenosine signaling and concomitant cardioprotection against IRI. Mice were exposed to myocardial ischemia and reperfusion injury. Myocardial injury was attenuated in mice treated with the nonspecific ENT inhibitor dipyridamole. A comparison of mice with global Ent1 or Ent2 deletion showed cardioprotection only in Ent1-/- mice. Moreover, studies with tissue-specific Ent deletion revealed that mice with myocyte-specific Ent1 deletion (Ent1loxP/loxP …

Genome-Wide Analyses Characterize Shared Heritability Among Cancers And Identify Novel Cancer Susceptibility Regions, Sara Lindström, Lu Wang, Helian Feng, Arunabha Majumdar, Sijia Huo, James Macdonald, Tabitha Harrison, Constance Turman, Hongjie Chen, Nicholas Mancuso, Theo Bammler, Breast Cancer Association Consortium (Bcac), Steve Gallinger, Stephen B Gruber, Marc J Gunter, Loic Le Marchand, Victor Moreno, Kenneth Offit, Colorectal Transdisciplinary Study (Corect), Colon Cancer Family Registry Study (Ccfr), Genetics And Epidemiology Of Colorectal Cancer Consortium (Gecco), Immaculata De Vivo, Tracy A O'Mara, Amanda B Spurdle, Ian Tomlinson, Endometrial Cancer Association Consortium (Ecac), Rebecca Fitzgerald, Puya Gharahkhani, Ines Gockel, Janusz Jankowski, Stuart Macgregor, Johannes Schumacher, Jill Barnholtz-Sloan, Melissa L Bondy, Richard S Houlston, Robert B Jenkins, Beatrice Melin, Margaret Wrensch, Paul Brennan, David C Christiani, Mattias Johansson, James Mckay, Melinda C Aldrich, Christopher I Amos, Maria Teresa Landi, Adonina Tardon, International Lung Cancer Consortium (Ilcco), D Timothy Bishop, Florence Demenais, Alisa M Goldstein, Mark M Iles, Peter A Kanetsky, Matthew H Law, Ovarian Cancer Association Consortium (Ocac), Laufey T Amundadottir, Rachael Stolzenberg-Solomon, Brian M Wolpin, Pancreatic Cancer Cohort Consortium (Panscan), Alison Klein, Gloria Petersen, Harvey Risch, Pancreatic Cancer Case-Control Consortium (Panc4), The Practical Consortium, Stephen J Chanock, Mark P Purdue, Ghislaine Scelo, Paul Pharoah, Siddhartha Kar, Rayjean J Hung, Bogdan Pasaniuc, Peter Kraft

Faculty, Staff and Student Publications

BACKGROUND: The shared inherited genetic contribution to risk of different cancers is not fully known. In this study, we leverage results from 12 cancer genome-wide association studies (GWAS) to quantify pairwise genome-wide genetic correlations across cancers and identify novel cancer susceptibility loci.

METHODS: We collected GWAS summary statistics for 12 solid cancers based on 376 759 participants with cancer and 532 864 participants without cancer of European ancestry. The included cancer types were breast, colorectal, endometrial, esophageal, glioma, head and neck, lung, melanoma, ovarian, pancreatic, prostate, and renal cancers. We conducted cross-cancer GWAS and transcriptome-wide association studies to discover novel …

Germline Genetic Variants And Pediatric Rhabdomyosarcoma Outcomes: A Report From The Children’S Oncology Group, Bailey A Martin-Giacalone, Melissa A Richard, Michael E Scheurer, Javed Khan, Pagna Sok, Priya B Shetty, Stephen J Chanock, Shengchao Alfred Li, Meredith Yeager, Deborah A Marquez-Do, Donald A Barkauskas, David Hall, Matthew T Mcevoy, Austin L Brown, Aniko Sabo, Paul Scheet, Chad D Huff, Stephen X Skapek, Douglas S Hawkins, Rajkumar Venkatramani, Lisa Mirabello, Philip J Lupo

Faculty, Staff and Student Publications

BACKGROUND: Relative to other pediatric cancers, survival for rhabdomyosarcoma (RMS) has not improved in recent decades, suggesting the need to enhance risk stratification. Therefore, we conducted a genome-wide association study for event-free survival (EFS) and overall survival (OS) to identify genetic variants associated with outcomes in individuals with RMS.

METHODS: The study included 920 individuals with newly diagnosed RMS who were enrolled in Children's Oncology Group protocols. To assess the association of each single nucleotide polymorphism (SNP) with EFS and OS, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs) using multivariable Cox proportional hazards models, adjusted for clinical …

Plumbing Mysterious Rnas In “Dark Genome” For The Conquest Of Human Diseases, Lisa A Huang, Chunru Lin, Liuqing Yang

Faculty, Staff and Student Publications

Next-generation sequencing has revealed that less than 2% of transcribed genes are translated into proteins, with a large portion transcribed into noncoding RNAs (ncRNAs). Among these, long noncoding RNAs (lncRNAs) represent the largest group and are pervasively transcribed throughout the genome. Dysfunctions in lncRNAs have been found in various diseases, highlighting their potential as therapeutic, diagnostic, and prognostic targets. However, challenges, such as unknown molecular mechanisms and nonspecific immune responses, and issues of drug specificity and delivery present obstacles in translating lncRNAs into clinical applications. In this review, we summarize recent publications that have explored lncRNA functions in human diseases. …

Decoding The Regulatory Roles Of Non-Coding Rnas In Cellular Metabolism And Disease, Yuru Zong, Xuliang Wang, Bing Cui, Xiaowei Xiong, Andrew Wu, Chunru Lin, Yaohua Zhang

Faculty, Staff and Student Publications

Non-coding RNAs, including long non-coding RNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are being studied extensively in a variety of fields. Their roles in metabolism have received increasing attention in recent years but are not yet clear. The regulation of glucose, fatty acid, and amino acid metabolism is an imperative physiological process that occurs in living organisms and takes part in cancer and cardiovascular diseases. Here, we summarize the important roles played by non-coding RNAs in glucose metabolism, fatty acid metabolism, and amino acid metabolism, as well as the mechanisms involved. We also summarize the therapeutic advances for non-coding …

Effect Of Porosity In Activated Carbon Supports For Silicon-Based Lithium-Ion Batteries (Libs), Yun Jeong Choi, Jeong Bin Choi, Ji Sun Im, Ji Hong Kim

Faculty, Staff and Student Publications

Activated carbon supports for Si deposition with different porosities were prepared, and the effect of porosity on the electrochemical characteristics was investigated. The porosity of the support is a key parameter affecting the Si deposition mechanism and the stability of the electrode. In the Si deposition mechanism, as the porosity of activated carbon increases, the effect of particle size reduction due to the uniform dispersion of Si was confirmed. This implies that the porosity of activated carbon can affect the rate performance. However, excessively high porosity reduced the contact area between Si and activated carbon, resulting in poor electrode stability. …

Targeting Cxcr4 Abrogates Resistance To Trastuzumab By Blocking Cell Cycle Progression And Synergizes With Docetaxel In Breast Cancer Treatment, Shuying Liu, Shelly M Xie, Wenbin Liu, Mihai Gagea, Ariella B Hanker, Nguyen Nguyen, Akshara Singareeka Raghavendra, Gloria Yang-Kolodji, Fuliang Chu, Sattva S Neelapu, Adriano Marchese, Samir Hanash, Johann Zimmermann, Carlos L Arteaga, Debasish Tripathy

Faculty, Staff and Student Publications

Background: Although trastuzumab and other HER2-targeted therapies have significantly improved survival in patients with HER2 overexpressed or amplified (HER2+) breast cancer, a significant proportion of patients do not respond or eventually develop clinical resistance. Strategies to reverse trastuzumab resistance remain a high clinical priority. We were the first to report the role of CXCR4 in trastuzumab resistance. The present study aims to explore the therapeutic potential of targeting CXCR4 and better understand the associated mechanisms.

Methods: Immunofluorescent staining, confocal microscopy analysis, and immunoblotting were used to analyze CXCR4 expression. BrdU incorporation assays and flow cytometry were used to analyze dynamic …

17Β-Estradiol Promotes Extracellular Vesicle Release And Selective Mirna Loading In Erα-Positive Breast Cancer, Rares Drula, Barbara Pardini, Xiao Fu, Mireia Cruz De Los Santos, Ancuta Jurj, Lan Pang, Sherien M El-Daly, Linda Fabris, Erik Knutsen, Mihnea P Dragomir, Recep Bayraktar, Yongfeng Li, Meng Chen, Filippo Del Vecchio, Léa Berland, Jessica Dae, Daniel Fan, Masayoshi Shimizu, Anh M Tran, Mercedes Barzi, Carlotta Pioppini, Angelica M Gutierrez, Cristina Ivan, Salyna Meas, Carolyn S Hall, Suresh K Alahari, Ioana Berindan-Neagoe, Muller Fabbri, Anthony Lucci, Banu Arun, Simone Anfossi, George A Calin

Faculty, Staff and Student Publications

The causes and consequences of abnormal biogenesis of extracellular vesicles (EVs) are not yet well understood in malignancies, including in breast cancers (BCs). Given the hormonal signaling dependence of estrogen receptor-positive (ER+) BC, we hypothesized that 17β-estradiol (estrogen) might influence EV production and microRNA (miRNA) loading. We report that physiological doses of 17β-estradiol promote EV secretion specifically from ER+ BC cells via inhibition of miR-149-5p, hindering its regulatory activity on SP1, a transcription factor that regulates the EV biogenesis factor nSMase2. Additionally, miR-149-5p downregulation promotes hnRNPA1 expression, responsible for the loading of let-7's miRNAs into EVs. In multiple patient cohorts, …

Non-Homologous End-Joining Pathway Genotypes Significantly Associated With Nasopharyngeal Carcinoma Susceptibility, Chia-Wen Tsai, Liang-Chun Shih, Wen-Shin Chang, Che-Lun Hsu, Jie-Long He, Te-Chun Hsia, Yun-Chi Wang, Jian Gu, Da-Tian Bau

Faculty, Staff and Student Publications

Defects in the non-homologous end-joining (NHEJ) DNA repair pathway lead to genomic instability and carcinogenesis. However, the roles of individual NHEJ genes in nasopharyngeal carcinoma (NPC) etiology are not well-understood. The aim of this study was to assess the contribution of NHEJ genotypes, including XRCC4 (rs6869366, rs3734091, rs28360071, rs28360317, rs1805377), XRCC5 (rs828907, rs11685387, rs9288518), XRCC6 (rs5751129, rs2267437, rs132770, rs132774), XRCC7 rs7003908, and Ligase4 rs1805388, to NPC risk, with 208 NPC patients and 416 controls. Genotype-phenotype correlations were also investigated by measuring mRNA and protein expression in adjacent normal tissues and assessing the NHEJ repair capacity in blood lymphocytes from 43 …

Genotype-Degree Of Hemolysis Correlation In Hereditary Spherocytosis, Yimeng Shi, Yuan Li, Xiawan Yang, Xiaoxia Li, Guangxin Peng, Xin Zhao, Xu Liu, Yufei Zhao, Jing Hu, Xiangrong Hu, Baohang Zhang, Kang Zhou, Yang Yang, Youzhen Xiong, Jianping Li, Huihui Fan, Wenrui Yang, Lei Ye, Liping Jing, Li Zhang, Fengkui Zhang

Faculty, Staff and Student Publications

BACKGROUND: Hereditary spherocytosis (HS) is a common inherited hemolytic anemia, caused by mutations in five genes that encode erythrocyte membrane skeleton proteins. The red blood cell (RBC) lifespan could directly reflect the degree of hemolysis. In the present cohort of 23 patients with HS, we performed next-generation sequencing (NGS) and Levitt's carbon monoxide (CO) breath test to investigate the potential genotype-degree of hemolysis correlation.

RESULTS: In the present cohort, we identified 8 ANK1,9 SPTB,5 SLC4A1 and 1 SPTA1 mutations in 23 patients with HS, and the median RBC lifespan was 14(8-48) days. The median RBC lifespan of patients with ANK1, …

Obstructive Sleep Apnea-Induced Hypertension Is Associated With Increased Gut And Neuroinflammation, Sriram Ayyaswamy, Huanan Shi, Bojun Zhang, Robert M Bryan, David J Durgan

Faculty, Staff and Students Publications

Background

Obstructive sleep apnea (OSA) is an independent risk factor for the development of hypertension. We have demonstrated that OSA induces gut dysbiosis, and this dysbiotic microbiota contributes to hypertension. However, the mechanisms linking gut dysbiosis to blood pressure regulation remain unclear. Recent studies demonstrate that gut dysbiosis can induce a proinflammatory response of the host resulting in peripheral and neuroinflammation, key factors in the development of hypertension. We hypothesized that OSA induces inflammation in the gut that contributes to neuroinflammation and hypertension.

Methods and Results

OSA was induced in 8‐week‐old male rats. After 2 weeks of apneas, lymphocytes were …

Steroid Receptor Coactivator 3 Is A Key Modulator Of Regulatory T Cell-Mediated Tumor Evasion, Sang Jun Han, Prashi Jain, Yosef Gilad, Yan Xia, Nuri Sung, Mi Jin Park, Adam M Dean, Rainer B Lanz, Jianming Xu, Clifford C Dacso, David M Lonard, Bert W O'Malley

Faculty, Staff and Students Publications

Steroid receptor coactivator 3 (SRC-3) is most strongly expressed in regulatory T cells (Tregs) and B cells, suggesting that it plays an important role in the regulation of Treg function. Using an aggressive E0771 mouse breast cell line syngeneic immune-intact murine model, we observed that breast tumors were "permanently eradicated" in a genetically engineered tamoxifen-inducible Treg-cell-specific SRC-3 knockout (KO) female mouse that does not possess a systemic autoimmune pathological phenotype. A similar eradication of tumor was noted in a syngeneic model of prostate cancer. A subsequent injection of additional E0771 cancer cells into these mice showed continued resistance to tumor …

Mapping Human Norovirus Antigens During Infection Reveals The Breadth Of The Humoral Immune Response, Lynn Su, Wanzhi Huang, Frederick H Neill, Mary K Estes, Robert L Atmar, Timothy Palzkill

Faculty, Staff and Students Publications

Human noroviruses (HuNoV) are the leading cause of acute gastroenteritis worldwide. The humoral immune response plays an important role in clearing HuNoV infections and elucidating the antigenic landscape of HuNoV during an infection can shed light on antibody targets to inform vaccine design. Here, we utilized Jun-Fos-assisted phage display of a HuNoV genogroup GI.1 genomic library and deep sequencing to simultaneously map the epitopes of serum antibodies of six individuals infected with GI.1 HuNoV. We found both unique and common epitopes that were widely distributed among both nonstructural proteins and the major capsid protein. Recurring epitope profiles suggest immunodominant antibody …

Author Correction: 3-Phosphoinositide-Dependent Kinase 1 Drives Acquired Resistance To Osimertinib, Ismail M Meraz, Mourad Majidi, Bingliang Fang, Feng Meng, Lihui Gao, Ruping Shao, Renduo Song, Feng Li, Yonathan Lissanu, Huiqin Chen, Min Jin Ha, Qi Wang, Jing Wang, Elizabeth Shpall, Sung Yun Jung, Franziska Haderk, Philippe Gui, Jonathan Wesley Riess, Victor Olivas, Trever G Bivona, Jack A Roth

Faculty, Staff and Students Publications

No abstract provided.

Variant Spectrum Of Von Hippel-Lindau Disease And Its Genomic Heterogeneity In Japan, Kenji Tamura, Yuki Kanazashi, Chiaki Kawada, Yuya Sekine, Kazuhiro Maejima, Shingo Ashida, Takashi Karashima, Shohei Kojima, Nickolas F Parrish, Shunichi Kosugi, Chikashi Terao, Shota Sasagawa, Masashi Fujita, Todd A Johnson, Yukihide Momozawa, Keiji Inoue, Taro Shuin, Hidewaki Nakagawa

Faculty, Staff and Student Publications

Von Hippel-Lindau (VHL) disease is an autosomal dominant, inherited syndrome with variants in the VHL gene, causing predisposition to multi-organ neoplasms with vessel abnormality. Germline variants in VHL can be detected in 80-90% of patients clinically diagnosed with VHL disease. Here, we summarize the results of genetic tests for 206 Japanese VHL families, and elucidate the molecular mechanisms of VHL disease, especially in variant-negative unsolved cases. Of the 206 families, genetic diagnosis was positive in 175 families (85%), including 134 families (65%) diagnosed by exon sequencing (15 novel variants) and 41 (20%) diagnosed by multiplex ligation-dependent probe amplification (MLPA) (one …

Bk Channel Modulation By Positively Charged Peptides And Auxiliary Γ Subunits Mediated By The Ca2+-Bowl Site, Guanxing Chen, Qin Li, Timothy I Webb, Mark A Hollywood, Jiusheng Yan

Faculty, Staff and Student Publications

The large-conductance, Ca2+-, and voltage-activated K+ (BK) channel consists of the pore-forming α (BKα) subunit and regulatory β and γ subunits. The γ1-3 subunits facilitate BK channel activation by shifting the voltage-dependence of channel activation toward the hyperpolarization direction by about 50-150 mV in the absence of Ca2+. We previously found that the intracellular C-terminal positively charged regions of the γ subunits play important roles in BK channel modulation. In this study, we found that the intracellular C-terminal region of BKα is indispensable in BK channel modulation by the γ1 subunit. Notably, synthetic peptide mimics of the γ1-3 subunits' C-terminal …

Autolysosomal Exocytosis Of Lipids Protect Neurons From Ferroptosis, Isha Ralhan, Jinlan Chang, Matthew J Moulton, Lindsey D Goodman, Nathanael Y J Lee, Greg Plummer, H Amalia Pasolli, Doreen Matthies, Hugo J Bellen, Maria S Ioannou

Faculty, Staff and Students Publications

During oxidative stress neurons release lipids that are internalized by glia. Defects in this coordinated process play an important role in several neurodegenerative diseases. Yet, the mechanisms of lipid release and its consequences on neuronal health are unclear. Here, we demonstrate that lipid-protein particle release by autolysosome exocytosis protects neurons from ferroptosis, a form of cell death driven by lipid peroxidation. We show that during oxidative stress, peroxidated lipids and iron are released from neurons by autolysosomal exocytosis which requires the exocytic machinery VAMP7 and syntaxin 4. We observe membrane-bound lipid-protein particles by TEM and demonstrate that these particles are …

Systematic Assessment Of The Contribution Of Structural Variants To Inherited Retinal Diseases, Shu Wen, Meng Wang, Xinye Qian, Yumei Li, Keqing Wang, Jongsu Choi, Mark E Pennesi, Paul Yang, Molly Marra, Robert K Koenekoop, Irma Lopez, Anna Matynia, Michael Gorin, Ruifang Sui, Fengxia Yao, Kerry Goetz, Fernanda Belga Ottoni Porto, Rui Chen

Faculty, Staff and Students Publications

Despite increasing success in determining genetic diagnosis for patients with inherited retinal diseases (IRDs), mutations in about 30% of the IRD cases remain unclear or unsettled after targeted gene panel or whole exome sequencing. In this study, we aimed to investigate the contributions of structural variants (SVs) to settling the molecular diagnosis of IRD with whole-genome sequencing (WGS). A cohort of 755 IRD patients whose pathogenic mutations remain undefined were subjected to WGS. Four SV calling algorithms including include MANTA, DELLY, LUMPY and CNVnator were used to detect SVs throughout the genome. All SVs identified by any one of these …

The Role Of Native Cysteine Residues In The Oligomerization Of Kcnq1 Channels, Alison Bates, Rebecca B Stowe, Elizabeth M Travis, Lauryn E Cook, Carole Dabney-Smith, Gary A Lorigan

Faculty, Staff and Student Publications

KCNQ1, the major component of the slow-delayed rectifier potassium channel, is responsible for repolarization of cardiac action potential. Mutations in this channel can lead to a variety of diseases, most notably long QT syndrome. It is currently unknown how many of these mutations change channel function and structure on a molecular level. Since tetramerization is key to proper function and structure of the channel, it is likely that mutations modify the stability of KCNQ1 oligomers. Presently, the C-terminal domain of KCNQ1 has been noted as the driving force for oligomer formation. However, truncated versions of this protein lacking the C-terminal …

Mitotrace: A Computational Framework For Analyzing Mitochondrial Variation In Single-Cell Rna Sequencing Data, Mingqiang Wang, Wankun Deng, David C Samuels, Zhongming Zhao, Lukas M Simon

Faculty, Staff and Student Publications

Genetic variation in the mitochondrial genome is linked to important biological functions and various human diseases. Recent progress in single-cell genomics has established single-cell RNA sequencing (scRNAseq) as a popular and powerful technique to profile transcriptomics at the cellular level. While most studies focus on deciphering gene expression, polymorphisms including mitochondrial variants can also be readily inferred from scRNAseq. However, limited attention has been paid to investigate the single-cell landscape of mitochondrial variants, despite the rapid accumulation of scRNAseq data in the community. In addition, a diploid context is assumed for most variant calling tools, which is not appropriate for …

Cfp1 Governs Uterine Epigenetic Landscapes To Intervene In Progesterone Responses For Uterine Physiology And Suppression Of Endometriosis, Seung Chel Yang, Mira Park, Kwon-Ho Hong, Hyeonwoo La, Chanhyeok Park, Peike Wang, Gaizhen Li, Qionghua Chen, Youngsok Choi, Francesco J Demayo, John P Lydon, David G Skalnik, Hyunjung J Lim, Seok-Ho Hong, So Hee Park, Yeon Sun Kim, Hye-Ryun Kim, Haengseok Song

Faculty, Staff and Students Publications

Progesterone (P4) is required for the preparation of the endometrium for a successful pregnancy. P4 resistance is a leading cause of the pathogenesis of endometrial disorders like endometriosis, often leading to infertility; however, the underlying epigenetic cause remains unclear. Here we demonstrate that CFP1, a regulator of H3K4me3, is required for maintaining epigenetic landscapes of P4-progesterone receptor (PGR) signaling networks in the mouse uterus. Cfp1f/f;Pgr-Cre (Cfp1d/d) mice showed impaired P4 responses, leading to complete failure of embryo implantation. mRNA and chromatin immunoprecipitation sequencing analyses showed that CFP1 regulates uterine mRNA profiles not only in H3K4me3-dependent …

Measuring The Acidification Of The Phagosomal Lumen In Live C Elegans Embryos, Omar Peña-Ramos, Zheng Zhou

Faculty, Staff and Students Publications

In metazoans, the acidification of the phagosomal lumen is essential for the efficient degradation of cargoes. Here, we present a protocol for measuring the rate of acidification inside phagosomal lumen containing apoptotic cells in living C. elegans embryos. We describe steps for generating a worm population, selecting embryos, and mounting embryos on agar pads. We then detail live imaging of embryos and data analysis. This protocol is applicable to any organism in which real-time fluorescence imaging can be performed. For complete details on the use and execution of this protocol, please refer to Pena-Ramos et al. (2022).