Medical Biochemistry Commons^™

Mucin 5ac Modulates Cancer-Associated Fibroblast Heterogeneity Through Epigenetic Reprogramming Of Precursor Cells, Rachel J. Kehrberg, Namita Bhyravbhatla, Zahraa Wajih Alsafwani, Xiaoqi Li, Gopalakrishnan Natarajan, Imran Khan, Randall E. Brand, Maneesh Jain, Surinder K. Batra, Sushil Kumar

Journal Articles: Biochemistry & Molecular Biology

Pancreatic cancer (PC) is characterized by extensive desmoplasia, with heterogeneous cancer-associated fibroblasts (CAFs) as a major component. However, the contribution of distinct precursor cells to CAF heterogeneity remains poorly defined. This study investigated the role of Muc5ac in modulating CAF heterogeneity by maturing precursor cells, including adipose-derived mesenchymal stem cells (AD-MSCs), bone marrow-derived MSCs (BM-MSCs), and pancreatic stellate cells (PSCs), into different CAF subsets. RNA sequencing of precursor cells treated with conditioned media from Muc5ac-proficient or -deficient cancer cells revealed distinct transcriptional profiles. Muc5ac significantly modulated the expression of Dnmts and Tets in AD-MSCs, promoting the acquisition of extracellular matrix …

Pancreatic Cancer Detection Consortium Biomarker Bakeoff: A Phase Ii Blinded Biomarker Validation And Panel Discovery Study, Ann L. Oberg, William R. Bamlet, Grant Izmirlian, Seetharaman Balasenthil, Surinder K. Batra, Masataka Hayashi, Daniel S. Herman, Michael A. Hollingsworth, Maneesh Jain, Ann M. Killary, Brianna M. Krusen, Suyu Liu, Shounak Majumder, Gopalakrishnan Natarajan, Subrata Sen, Lynette M. Smith, Sudhir Srivastava, Brian M. Wolpin, Kenneth S. Zaret, Michael G. Goggins

Journal Articles: Biochemistry & Molecular Biology

PURPOSE: The Pancreatic Cancer Detection Consortium (PCDC) performed a blinded Early Detection Research Network-defined phase II biomarker bakeoff study of blood-based biomarker panels. The aims were to evaluate panel performance, to compare the panels' performance with that of cancer antigen 19-9 (CA19-9) alone, and to evaluate the performance of new combinations of the individual biomarkers.

EXPERIMENTAL DESIGN: Ten biomarkers representing eight biomarker panels and CA19-9 were evaluated using plasma, serum, and germline DNA from 140 stage I to IV pancreatic ductal adenocarcinoma (PDAC) cases and 140 controls from three tertiary care institutions, with controls frequency matched to cases on age …

Overcoming Radiation Resistance: Ferroptosis Induction To Sensitize Solid Tumors To Radiation Therapy, Joseph Carmicheal, Caden M. Fritson, Alexandra Seas, Heidi M. Vieira, Surinder K. Batra

Journal Articles: Biochemistry & Molecular Biology

Radiation therapy (RT) is a mainstay of treatment for a myriad of cancers, often utilized for tumors that are unable to be resected, as well as an adjunct to surgery and chemotherapy. Unfortunately, many cancers are resistant to RT-induced damage and subsequent cell death. This has spurred the pursuit of novel radiation sensitizers that could potentiate the effects of this widely used and important treatment modality. Since its discovery as a regulated cell death mechanism in 2012, ferroptosis has been studied for its connection to cancer and other known oxidative pathways. With this, the interplay between RT and ferroptosis in …

Steps Toward Clinical Validation Of Exhaled Volatile Organic Compound Biomarkers For Hypoglycemia In Persons With Type 1 Diabetes., Mark Woollam, Paula Angarita-Rivera, Sanskar Thakur, Ali Daneshkhah, Amanda P Siegel, Dana S Hardin, Mangilal Agarwal

Ambulatory and Primary Care Articles

Persons with type 1 diabetes (T1D) must track/control their blood glucose (BG) levels to avoid hypoglycemic events (BG <  70 mg/dL), which in the most severe cases can lead to seizures or even death. Canines may lead the way toward innovative testing solutions, as they can be trained to identify hypoglycemia simply and noninvasively by smelling exhaled volatile organic compounds (VOCs). To identify breath-based biomarkers of hypoglycemia, samples were collected during two consecutive summers at a diabetes camp (Cohort 1 and Cohort 2), and VOCs were analyzed by gas chromatography-mass spectrometry. Conserved VOCs between the two cohorts were identified, but individual VOCs alone had low accuracies for detection. Therefore, supervised multivariate statistical analysis was undertaken to identify a biosignature in the training data set (Cohort 1) that could detect hypoglycemia with higher accuracy (sensitivity = 94.8%/specificity = 95.0%). When this model was blindly tested on Cohort 2, hypoglycemia was classified with sensitivity = 90.0%/specificity = 89.9%. Ultimately, this study makes strides toward clinical validation through verifying biomarkers of hypoglycemia in hundreds of breath samples. These results may be translated to design a sensor array that could be integrated into a portable breathalyzer to increase glycemic control in persons with T1D.

Ion-Dna Interactions As A Key Determinant Of Uracil Dna Glycosylase Activity., Sharon N Greenwood, Alexis N Dispensa, Matthew Wang, Justin R Bauer, Timothy D Vaden, Zhiwei Liu, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Because of their ubiquitous presence, ions interact with numerous macromolecules in the cell and affect critical biological processes. Here, we discuss how cations including Mg²⁺ alter the enzymatic activity of a DNA glycosylase by tuning its affinity for DNA. The response of uracil DNA glycosylase (UNG2) to Mg²⁺ ions in solution is biphasic and paradoxical, where low concentrations of the ion stimulate the enzyme, but high concentrations inhibit the enzyme. We analyzed this phenomenon by modeling experimental data with a statistical framework that we empirically derived to understand molecular systems that display biphasic behaviors. Parameters from our statistical …

St6galnac-I Regulates Tumor Cell Sialylation Via Nectin2/Muc5ac-Mediated Immunosuppression And Angiogenesis In Non-Small Cell Lung Cancer, Muthamil Iniyan Appadurai, Sanjib Chaudhary, Ashu Shah, Gopalakrishnan Natarajan, Zahraa W. Alsafwani, Parvez Khan, Dhananjay D. Shinde, Subodh M. Lele, Lynette M. Smith, Mohd W. Nasser, Surinder K. Batra, Apar Kishor Ganti, Imayavaramban Lakshmanan

Journal Articles: Biochemistry & Molecular Biology

Glycosylation controls immune evasion, tumor progression, and metastasis. However, how tumor cell sialylation regulates immune evasion remains poorly characterized. ST6GalNAc-I, a sialyltransferase that conjugates sialic acid to the glycans in glycoproteins, was overexpressed in an aggressive-type KPA (KrasG12D/+ Trp53R172H/+ Ad-Cre) lung adenocarcinoma (LUAD) model and patient samples. Proteomic and biochemical analysis indicated that ST6GalNAc-I mediated NECTIN2 sialylation in LUAD cells. ST6GalNAc-I-deficient tumor cells cocultured with T cells were more susceptible to T cell-mediated tumor cell killing, indicating a key role for NECTIN2 in T cell dysfunction. Mice injected with St6galnac-I-knockdown syngeneic cells showed reduced lung tumor incidence and Nectin2/Tigit-associated immunosuppression. …

Structural And Molecular Basis Of Pcna-Activated Fan1 Nuclease Function In Dna Repair, F. Li, A. S. Phadte, M. Bhatia, S. Barndt, A.R. Monte Carlo, Iii, C.F.D. Hou, R. Yang, S. Strock, A. Pluciennik

Department of Biochemistry and Molecular Biology Faculty Papers

FAN1 is a DNA dependent nuclease whose proper function is essential for maintaining human health. For example, a genetic variant in FAN1, Arg507 to His hastens onset of Huntington's disease, a repeat expansion disorder for which there is no cure. How the Arg507His mutation affects FAN1 structure and enzymatic function is unknown. Using cryo-EM and biochemistry, we have discovered that FAN1 arginine 507 is critical for its interaction with PCNA, and mutation of Arg507 to His attenuates assembly of the FAN1-PCNA complex on a disease-relevant extrahelical DNA extrusions formed within DNA repeats. This mutation concomitantly abolishes PCNA-FAN1-dependent cleavage of such …

Contract To Kill: Gnas Mutation, Pratima Raut, Poompozhil Mathivanan, Surinder K. Batra, Moorthy P. Ponnusamy

Journal Articles: Biochemistry & Molecular Biology

The mutation in Gsα-coding GNAS exons, popular as gsp oncogene, is the most frequent mutation across all heterotrimeric G proteins involved in oncogenesis. GNAS R201, the most frequently mutated, followed by Q227, are found predominantly across various neoplasms and cancers such as IPMN, pituitary, thyroid, appendiceal, colorectal, etc. This review emphasizes the pivotal significance of the gsp oncogene and its ramifications underpinning the sustained addiction to GNAS mutation. Recent studies delineating the mechanistic intricacies that provide solid evidence of the profound impact of oncogenic GNAS on tumor formation, progression, and maintenance are highlighted. We have leveraged the discoveries of Gsα …

Proteomics Profiling Of Research Models For Studying Pancreatic Ductal Adenocarcinoma, Mathilde Resell, Hanne-Line Rabben, Animesh Sharma, Lars Hagen, Linh Hoang, Nan T. Skogaker, Anne Aarvik, Eirik Knudsen Bjåstad, Magnus K. Svensson, Manoj Amrutkar, Caroline S. Verbeke, Surinder K. Batra, Gunnar Qvigstad, Timothy C. Wang, Anil Rustgi, Duan Chen, Chun-Mei Zhao

Journal Articles: Biochemistry & Molecular Biology

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal malignancies, with a five-year survival rate of 10-15% due to late-stage diagnosis and limited efficacy of existing treatments. This study utilized proteomics-based systems modelling to generate multimodal datasets from various research models, including PDAC cells, spheroids, organoids, and tissues derived from murine and human samples. Identical mass spectrometry-based proteomics was applied across the different models. The preparation and validation of the research models and the proteomics were described in detail. The assembly datasets we present here contribute to the data collection on PDAC, which will be useful for systems modelling, …

Space: An Open-Source, Single-Cell Analysis Of Cell Painting Data, Fabio Stossi, Pankaj K Singh, Michela Marini, Kazem Safari, Adam T Szafran, Alejandra Rivera Tostado, Christopher D Candler, Maureen G Mancini, Elina A Mosa, Michael J Bolt, Demetrio Labate, Michael A Mancini

Faculty, Staff and Students Publications

Phenotypic profiling by high throughput microscopy, including Cell Painting, has become a leading tool for screening large sets of perturbations in cellular models. To efficiently analyze this big data, available open-source software requires computational resources usually not available to most laboratories. In addition, the cell-to-cell variation of responses within a population, while collected and analyzed, is usually averaged and unused. We introduce SPACe (Swift Phenotypic Analysis of Cells), an open-source platform for analysis of single-cell image-based morphological profiles produced by Cell Painting. We highlight several advantages of SPACe, including processing speed, accuracy in mechanism of action recognition, reproducibility across biological …

Znf397 Deficiency Triggers Tet2-Driven Lineage Plasticity And Ar-Targeted Therapy Resistance In Prostate Cancer, Yaru Xu, Yuqiu Yang, Zhaoning Wang, Martin Sjöström, Yuyin Jiang, Yitao Tang, Siyuan Cheng, Su Deng, Choushi Wang, Julisa Gonzalez, Nickolas A Johnson, Xiang Li, Xiaoling Li, Lauren A Metang, Atreyi Mukherji, Quanhui Xu, Carla R Tirado, Garrett Wainwright, Xinzhe Yu, Spencer Barnes, Mia Hofstad, Yu Chen, Hong Zhu, Ariella B Hanker, Ganesh V Raj, Guanghui Zhu, Housheng H He, Zhao Wang, Carlos L Arteaga, Han Liang, Felix Y Feng, Yunguan Wang, Tao Wang, Ping Mu

Faculty, Staff and Students Publications

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming that allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified zinc finger protein 397 (ZNF397) as a bona fide coactivator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a ten-eleven translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our …

A Biallelic Variant Of The Rna Exosome Gene, Exosc4, Associated With Neurodevelopmental Defects Impairs Rna Exosome Function And Translation, Milo B Fasken, Sara W Leung, Lauryn A Cureton, Maha Al-Awadi, Adila Al-Kindy, Ambro Van Hoof, Sohail Khoshnevis, Homa Ghalei, Almundher Al-Maawali, Anita H Corbett

Faculty, Staff and Student Publications

The RNA exosome is an evolutionarily conserved complex required for both precise RNA processing and decay. Pathogenic variants in EXOSC genes, which encode structural subunits of this complex, are linked to several autosomal recessive disorders. Here, we describe a missense allele of the EXOSC4 gene that causes a collection of clinical features in two affected siblings. This missense variant (NM_019037.3: exon3:c.560T>C) changes a leucine residue within a conserved region of EXOSC4 to proline (p.Leu187Pro). The two affected individuals show prenatal growth restriction, failure to thrive, global developmental delay, intracerebral and basal ganglia calcifications, and kidney failure. Homozygosity for the …

Genetic Diversity Of 1,845 Rhesus Macaques Improves Genetic Variation Interpretation And Identifies Disease Models, Jun Wang, Meng Wang, Ala Moshiri, R Alan Harris, Muthuswamy Raveendran, Tracy Nguyen, Soohyun Kim, Laura Young, Keqing Wang, Roger Wiseman, David H O'Connor, Zach Johnson, Melween Martinez, Michael J Montague, Ken Sayers, Martha Lyke, Eric Vallender, Tim Stout, Yumei Li, Sara M Thomasy, Jeffrey Rogers, Rui Chen

Faculty, Staff and Students Publications

Understanding and treating human diseases require valid animal models. Leveraging the genetic diversity in rhesus macaque populations across eight primate centers in the United States, we conduct targeted-sequencing on 1845 individuals for 374 genes linked to inherited human retinal and neurodevelopmental diseases. We identify over 47,000 single nucleotide variants, a substantial proportion of which are shared with human populations. By combining rhesus and human allele frequencies with established variant prediction methods, we develop a machine learning-based score that outperforms established methods in predicting missense variant pathogenicity. Remarkably, we find a marked number of loss-of-function variants and putative deleterious variants, which …

Successful Management Of Chromoblastomycosis Utilizing Conventional Antifungal Agents And Imiquimod Therapy, Jinjin Zheng, Shougang Liu, Zhenmou Xie, Yangxia Chen, Liyan Xi, Hongfang Liu, Yinghui Liu

Faculty, Staff and Student Publications

Chromoblastomycosis (CBM), a chronic fungal infection affecting the skin and subcutaneous tissues, is predominantly caused by dematiaceous fungi in tropical and subtropical areas. Characteristically, CBM presents as plaques and nodules, often leading to scarring post-healing. Besides traditional diagnostic methods such as fungal microscopy, culture, and histopathology, dermatoscopy and reflectance confocal microscopy can aid in diagnosis. The treatment of CBM is an extended and protracted process. Imiquimod, acting as an immune response modifier, boosts the host's immune response against CBM, and controls scar hyperplasia, thereby reducing the treatment duration. We present a case of CBM in Guangdong with characteristic reflectance confocal …

Cyp3a Mediates An Unusual C(Sp2)-C(Sp3) Bond Cleavage Via Ipso-Addition Of Oxygen In Drug Metabolism, Xuan Qin, Yong Wang, Qiuji Ye, John M Hakenjos, Jin Wang, Mingxing Teng, Lei Guo, Zhi Tan, Damian W Young, Kevin R Mackenzie, Feng Li

Faculty, Staff and Students Publications

Mammalian cytochrome P450 drug-metabolizing enzymes rarely cleave carbon–carbon (C-C) bonds and the mechanisms of such cleavages are largely unknown. We identified two unusual cleavages of non-polar, unstrained C(sp2)-C(sp3) bonds in the FDA-approved tyrosine kinase inhibitor pexidartinib that are mediated by CYP3A4/5, the major human phase I drug metabolizing enzymes. Using a synthetic ketone, we rule out the Baeyer-Villiger oxidation mechanism that is commonly invoked to address P450-mediated C-C bond cleavages. Our studies in 18O2 and H218O enriched systems reveal two unusual distinct mechanisms of C-C bond cleavage: one bond is cleaved by CYP3A-mediated ipso-addition of oxygen to a C(sp2) …

Utility Of Peripheral Protein Biomarkers For The Prediction Of Incident Interstitial Features: A Multicentre Retrospective Cohort Study, Samuel Ash, Tracy J Doyle, Bina Choi, Ruben San Jose Estepar, Victor Castro, Nicholas Enzer, Ravi Kalhan, Gabrielle Liu, Russell Bowler, David O Wilson, Raul San Jose Estepar, Ivan O Rosas, George R Washko

Faculty, Staff and Students Publications

INTRODUCTION/RATIONALE: Protein biomarkers may help enable the prediction of incident interstitial features on chest CT.

METHODS: We identified which protein biomarkers in a cohort of smokers (COPDGene) differed between those with and without objectively measured interstitial features at baseline using a univariate screen (t-test false discovery rate, FDR p

RESULTS: In COPDGene, 1305 biomarkers were available and 20 differed between those with and without interstitial features at baseline. Of these, 11 were associated with feature progression over a mean of 5.5 years of follow-up, and of these 4 were available in PLuSS, (angiopoietin-2, matrix metalloproteinase 7, macrophage inflammatory protein 1 …

A Mutation In F-Actin Polymerization Factor Suppresses The Distal Arthrogryposis Type 5 Piezo2 Pathogenic Variant In Caenorhabditis Elegans, Xiaofei Bai, Harold E Smith, Luis O Romero, Briar Bell, Valeria Vásquez, Andy Golden

Faculty, Staff and Student Publications

The mechanosensitive PIEZO channel family has been linked to over 26 disorders and diseases. Although progress has been made in understanding these channels at the structural and functional levels, the underlying mechanisms of PIEZO-associated diseases remain elusive. In this study, we engineered four PIEZO-based disease models using CRISPR/Cas9 gene editing. We performed an unbiased chemical mutagen-based genetic suppressor screen to identify putative suppressors of a conserved gain-of-function variant pezo-1[R2405P] that in human PIEZO2 causes distal arthrogryposis type 5 (DA5; p. R2718P). Electrophysiological analyses indicate that pezo-1(R2405P) is a gain-of-function allele. Using genomic mapping and whole-genome sequencing approaches, we identified a …

Efficacy Of Supplemental Ultrasound-Guided Pericapsular Nerve Group (Peng) Block Combined With Lateral Femoral Cutaneous Nerve Block In Patients Receiving Local Infiltration Analgesia After Hip Fracture Surgery: A Prospective Randomized Controlled Trial, Seung-Hee Yoo, Min-Jin Lee, Min-Hyouk Beak, Won-Joong Kim

Faculty, Staff and Student Publications

No abstract provided.

Bispecific Bcma/Cd24 Car-T Cells Control Multiple Myeloma Growth, Fumou Sun, Yan Cheng, Visanu Wanchai, Wancheng Guo, David Mery, Hongwei Xu, Dongzheng Gai, Eric Siegel, Clyde Bailey, Cody Ashby, Samer Al Hadidi, Carolina Schinke, Sharmilan Thanendrarajan, Yupo Ma, Qing Yi, Robert Z Orlowski, Maurizio Zangari, Frits Van Rhee, Siegfried Janz, Gail Bishop, Guido Tricot, John D Shaughnessy, Fenghuang Zhan

Faculty, Staff and Student Publications

Anti-multiple myeloma B cell maturation antigen (BCMA)-specific chimeric antigen receptor (CAR) T-cell therapies represent a promising treatment strategy with high response rates in myeloma. However, durable cures following anti-BCMA CAR-T cell treatment of myeloma are rare. One potential reason is that a small subset of minimal residual myeloma cells seeds relapse. Residual myeloma cells following BCMA-CAR-T-mediated treatment show less-differentiated features and express stem-like genes, including CD24. CD24-positive myeloma cells represent a large fraction of residual myeloma cells after BCMA-CAR-T therapy. In this work, we develop CD24-CAR-T cells and test their ability to eliminate myeloma cells. We find that CD24-CAR-T cells …

Structural Basis For Nuclear Import Of Hepatitis B Virus (Hbv) Nucleocapsid Core, Ruoyu Yang, Ying-Hui Ko, Fenglin Li, Ravi K. Lokareddy, Chun-Feng David Hou, Christine Kim, Shelby Klein, Santiago Antolínez, Juan F. Marín, Carolina Pérez-Segura, Martin F. Jarrold, Adam Zlotnick, Jodi A. Hadden-Perilla, Gino Cingolani

Student Papers, Posters & Projects

Nuclear import of the hepatitis B virus (HBV) nucleocapsid is essential for replication that occurs in the nucleus. The ~360-angstrom HBV capsid translocates to the nuclear pore complex (NPC) as an intact particle, hijacking human importins in a reaction stimulated by host kinases. This paper describes the mechanisms of HBV capsid recognition by importins. We found that importin α1 binds a nuclear localization signal (NLS) at the far end of the HBV coat protein Cp183 carboxyl-terminal domain (CTD). This NLS is exposed to the capsid surface through a pore at the icosahedral quasi-sixfold vertex. Phosphorylation at serine-155, serine-162, and serine-170 …

Understanding The Function Of Pax5 In Development Of Docetaxel-Resistant Neuroendocrine-Like Prostate Cancers, Sreyashi Bhattacharya, Hannah Harris, Ridwan Islam, Sanika Bodas, Navatha S. Polavaram, Juhi Mishra, Dipanwita Das, Parthasarathy Seshacharyulu, Achyuth Kalluchi, Anirban Pal, Manish Kohli, Subodh M. Lele, Michael Muders, Surinder K. Batra, Paramita M. Ghosh, Kaustubh Datta, M. Jordan Rowley, Samikshan Dutta

Journal Articles: Biochemistry & Molecular Biology

Resistance to the current Androgen Receptor Signaling Inhibitor (ARSI) therapies has led to higher incidences of therapy-induced neuroendocrine-like prostate cancer (t-NEPC). This highly aggressive subtype with predominant small-cell-like characteristics is resistant to taxane chemotherapies and has a dismal overall survival. t-NEPCs are mostly treated with platinum-based drugs with a combination of etoposide or taxane and have less selectivity and high systemic toxicity, which often limit their clinical potential. During t-NEPC transformation, adenocarcinomas lose their luminal features and adopt neuro-basal characteristics. Whether the adaptive neuronal characteristics of t-NEPC are responsible for such taxane resistance remains unknown. Pathway analysis from patient gene-expression …

The Expression Of The Claudin Family Of Proteins In Colorectal Cancer, Kristin E. Cox, Shanglei Liu, Robert M. Hoffman, Surinder K. Batra, Punita Dhawan, Michael Bouvet

Journal Articles: Biochemistry & Molecular Biology

Claudins (CLDN1-CLDN24) are a family of tight junction proteins whose dysregulation has been implicated in tumorigeneses of many cancer types. In colorectal cancer (CRC), CLDN1, CLDN2, CLDN4, and CLDN18 have been shown to either be upregulated or aberrantly expressed. In the normal colon, CLDN1 and CLDN3-7 are expressed. Although a few claudins, such as CLDN6 and CLDN7, are expressed in CRC their levels are reduced compared to the normal colon. The present review outlines the expression profiles of claudin proteins in CRC and those that are potential biomarkers for prognostication.

Effects Of Dimerization On The Deacylase Activities Of Human Sirt2., Jie Yang, Nathan I Nicely, Brian P Weiser

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Human sirtuin isoform 2 (SIRT2) is an NAD+-dependent enzyme that functions as a lysine deacetylase and defatty-acylase. Here, we report that SIRT2 readily dimerizes in solution and in cells and that dimerization affects its ability to remove different acyl modifications from substrates. Dimerization of recombinant SIRT2 was revealed with analytical size exclusion chromatography and chemical cross-linking. Dimerized SIRT2 dissociates into monomers upon binding long fatty acylated substrates (decanoyl-, dodecanoyl-, and myristoyl-lysine). However, we did not observe dissociation of dimeric SIRT2 in the presence of acetyl-lysine. Analysis of X-ray crystal structures led us to discover a SIRT2 double mutant (Q142A/E340A) that …

Localization, Tissue Biology, And T Cell State — Implications For Cancer Immunotherapy, Jason M Schenkel, Kristen E Pauken

Faculty, Staff and Student Publications

Tissue localization is a critical determinant of T cell immunity. CD8+ T cells are contact-dependent killers, which requires them to physically be within the tissue of interest to kill peptide-MHC class I-bearing target cells. Following their migration and extravasation into tissues, T cells receive many extrinsic cues from the local microenvironment, and these signals shape T cell differentiation, fate and function. Because major organ systems are variable in their functions and compositions, they apply disparate pressures on T cells to adapt to the local microenvironment. Additional complexity arises in the context of malignant lesions (either primary or metastatic), and this …

Age- And Sex-Specific Reference Values Of Biventricular Flow Components And Kinetic Energy By 4d Flow Cardiovascular Magnetic Resonance In Healthy Subjects, Xiaodan Zhao, Ru-San Tan, Pankaj Garg, Ping Chai, Shuang Leng, Jennifer Ann Bryant, Lynette L S Teo, Tee Joo Yeo, Marielle V Fortier, Ting Ting Low, Ching Ching Ong, Shuo Zhang, Rob J Van Der Geest, John C Allen, Teng Hong Tan, James W Yip, Ju Le Tan, Marina Hughes, Sven Plein, Jos J M Westenberg, Liang Zhong

Faculty, Staff and Student Publications

BACKGROUND: Advances in four-dimensional flow cardiovascular magnetic resonance (4D flow CMR) have allowed quantification of left ventricular (LV) and right ventricular (RV) blood flow. We aimed to (1) investigate age and sex differences of 4D flow CMR-derived LV and RV relative flow components and kinetic energy (KE) parameters indexed to end-diastolic volume (KEi

METHODS: We performed 4D flow analysis in 163 healthy participants (42% female; mean age 43 ± 13 years) of a prospective registry study (NCT03217240) who were free of cardiovascular diseases. Relative flow components (direct flow, retained inflow, delayed ejection flow, residual volume) and multiple phasic KEi

RESULTS: …

Fan1 Removes Triplet Repeat Extrusions Via A Pcna- And Rfc-Dependent Mechanism, Ashutosh S. Phadte, Mayuri Bhatia, Hope Ebert, Haaris Abdullah, Essam Abed Elrazaq, Konstantin E. Komolov, Anna Pluciennik

Department of Biochemistry and Molecular Biology Faculty Papers

Human genome-wide association studies have identified FAN1 and several DNA mismatch repair (MMR) genes as modifiers of Huntington’s disease age of onset. In animal models, FAN1 prevents somatic expansion of CAG triplet repeats, whereas MMR proteins promote this process. To understand the molecular basis of these opposing effects, we evaluated FAN1 nuclease function on DNA extrahelical extrusions that represent key intermediates in triplet repeat expansion. Here, we describe a strand-directed, extrusion-provoked nuclease function of FAN1 that is activated by RFC, PCNA, and ATP at physiological ionic strength. Activation of FAN1 in this manner results in DNA cleavage in the vicinity …

Machine Learning For Ecg Diagnosis And Risk Stratification Of Occlusion Myocardial Infarction, Salah S Al-Zaiti, Christian Martin-Gill, Jessica K Zègre-Hemsey, Zeineb Bouzid, Ziad Faramand, Mohammad O Alrawashdeh, Richard E Gregg, Stephanie Helman, Nathan T Riek, Karina Kraevsky-Phillips, Gilles Clermont, Murat Akcakaya, Susan M Sereika, Peter Van Dam, Stephen W Smith, Yochai Birnbaum, Samir Saba, Ervin Sejdic, Clifton W Callaway

Faculty, Staff and Students Publications

Patients with occlusion myocardial infarction (OMI) and no ST-elevation on presenting electrocardiogram (ECG) are increasing in numbers. These patients have a poor prognosis and would benefit from immediate reperfusion therapy, but, currently, there are no accurate tools to identify them during initial triage. Here we report, to our knowledge, the first observational cohort study to develop machine learning models for the ECG diagnosis of OMI. Using 7,313 consecutive patients from multiple clinical sites, we derived and externally validated an intelligent model that outperformed practicing clinicians and other widely used commercial interpretation systems, substantially boosting both precision and sensitivity. Our derived …

Advancing Asms With Lc-Ms/Ms For The Discovery Of Novel Pdcl2 Ligands From Dna-Encoded Chemical Library Selections, Qiuji Ye, Hassane Belabed, Yong Wang, Zhifeng Yu, Murugesan Palaniappan, Jian-Yuan Li, Stacey A Kalovidouris, Kevin R Mackenzie, Mingxing Teng, Damian W Young, Yoshitaka Fujihara, Martin M Matzuk

Faculty, Staff and Students Publications

BACKGROUND: A safe, effective, and reversible nonhormonal male contraceptive drug is greatly needed for male contraception as well as for circumventing the side effects of female hormonal contraceptives. Phosducin-like 2 (PDCL2) is a testis-specific phosphoprotein in mice and humans. We recently found that male PDCL2 knockout mice are sterile due to globozoospermia caused by impaired sperm head formation, indicating that PDCL2 is a potential target for male contraception. Herein, our study for the first time developed a biophysical assay for PDCL2 allowing us to screen a series of small molecules, to study structure-activity relationships, and to discover two PDCL2 binders …

A Computationally Designed Ace2 Decoy Has Broad Efficacy Against Sars-Cov-2 Omicron Variants And Related Viruses In Vitro And In Vivo, Brandon Havranek, Graeme Walker Lindsey, Yusuke Higuchi, Yumi Itoh, Tatsuya Suzuki, Toru Okamoto, Atsushi Hoshino, Erik Procko, Shahidul M. Islam

SKMC Student Presentations and Publications

SARS-CoV-2, especially B.1.1.529/omicron and its sublineages, continues to mutate to evade monoclonal antibodies and antibodies elicited by vaccination. Affinity-enhanced soluble ACE2 (sACE2) is an alternative strategy that works by binding the SARS-CoV-2 S protein, acting as a 'decoy' to block the interaction between the S and human ACE2. Using a computational design strategy, we designed an affinity-enhanced ACE2 decoy, FLIF, that exhibited tight binding to SARS-CoV-2 delta and omicron variants. Our computationally calculated absolute binding free energies (ABFE) between sACE2:SARS-CoV-2 S proteins and their variants showed excellent agreement to binding experiments. FLIF displayed robust therapeutic utility against a broad range …

The Wnt/Pcp Formin Daam1 Drives Cell-Cell Adhesion During Nephron Development, Heather S Carr, Yan Zuo, Jeffrey A Frost

Faculty, Staff and Student Publications

The Somatostatin receptor 2 (Sstr2) is a heterotrimeric G protein-coupled receptor that is highly expressed in neuroendocrine tumors and is a common pharmacological target for intervention. Unfortunately, not all neuroendocrine tumors express Sstr2, and Sstr2 expression can be downregulated with prolonged agonist use. Sstr2 is rapidly internalized following agonist stimulation and, in the short term, is quantitatively recycled back to the plasma membrane. However, mechanisms controlling steady state expression of Sstr2 in the absence of agonist are less well described. Here, we show that Sstr2 interacts with the Wnt pathway protein Dvl1 in a ligand-independent manner to target Sstr2 for …