Biochemistry, Biophysics, and Structural Biology Commons^™

A Small-Molecule Inhibitor Of Topbp1 Exerts Anti-Myc Activity And Synergy With Parp Inhibitors, Fang-Tsyr Lin, Kang Liu, Lidija A Wilhelms Garan, Helena Folly-Kossi, Yongcheng Song, Shwu-Jiuan Lin, Weei-Chin Lin

Faculty, Staff and Students Publications

We have previously identified TopBP1 (topoisomerase IIβ-binding protein 1) as a promising target for cancer therapy, given its role in the convergence of Rb, PI(3)K/Akt, and p53 pathways. Based on this, we conducted a large-scale molecular docking screening to identify a small-molecule inhibitor that specifically targets the BRCT7/8 domains of TopBP1, which we have named 5D4. Our studies show that 5D4 inhibits TopBP1 interactions with E2F1, mutant p53, and Cancerous Inhibitor of Protein Phosphatase 2A. This leads to the activation of E2F1-mediated apoptosis and the inhibition of mutant p53 gain of function. In addition, 5D4 disrupts the interaction of TopBP1 …

Widefield Imaging Of Rapid Pan-Cortical Voltage Dynamics With An Indicator Evolved For One-Photon Microscopy, Xiaoyu Lu, Yunmiao Wang, Zhuohe Liu, Yueyang Gou, Dieter Jaeger, François St-Pierre

Faculty, Staff and Students Publications

Widefield imaging with genetically encoded voltage indicators (GEVIs) is a promising approach for understanding the role of large cortical networks in the neural coding of behavior. However, the limited performance of current GEVIs restricts their deployment for single-trial imaging of rapid neuronal voltage dynamics. Here, we developed a high-throughput platform to screen for GEVIs that combine fast kinetics with high brightness, sensitivity, and photostability under widefield one-photon illumination. Rounds of directed evolution produced JEDI-1P, a green-emitting fluorescent indicator with enhanced performance across all metrics. Next, we optimized a neonatal intracerebroventricular delivery method to achieve cost-effective and wide-spread JEDI-1P expression in …

Opposing Roles For The Α Isoform Of The Catalytic Subunit Of Protein Phosphatase 1 In Inside-Out And Outside-In Integrin Signaling In Murine Platelets, Tanvir Khatlani, Subhashree Pradhan, Kimberly Langlois, Deepika Subramanyam, Rolando E Rumbaut, K Vinod Vijayan

Faculty, Staff and Students Publications

Platelet activation during hemostasis and thrombosis is facilitated by agonist-induced inside–out and integrin αIIbβ3-initiated outside–in signaling via protein kinases and phosphatases. Pharmacological inhibitor studies suggest that the serine/threonine protein phosphatase 1 (PP1) promotes platelet activation. However, since phosphatase inhibitors block all the isoforms of the catalytic subunit of PP1 (PP1c), the role of specific PP1c isoform in platelet signaling remains unclear. Here, we employed a platelet-specific PP1cα−/− mice to explore the contribution of a major PP1 isoform in platelet functions. Loss of PP1cα moderately decreased activation of integrin αIIbβ3, binding of soluble fibrinogen, and aggregation to low-dose thrombin, ADP, and …

Global Effect Of Modifiable Risk Factors On Cardiovascular Disease And Mortality, Global Cardiovascular Risk Consortium, Christina Magnussen, Francisco M Ojeda, Darryl P Leong, Jesus Alegre-Diaz, Philippe Amouyel, Larissa Aviles-Santa, Dirk De Bacquer, Christie M Ballantyne, Antonio Bernabé-Ortiz, Martin Bobak, Hermann Brenner, Rodrigo M Carrillo-Larco, James De Lemos, Annette Dobson, Marcus Dörr, Chiara Donfrancesco, Wojciech Drygas, Robin P Dullaart, Gunnar Engström, Marco M Ferrario, Jean Ferrières, Giovanni De Gaetano, Uri Goldbourt, Clicerio Gonzalez, Guido Grassi, Allison M Hodge, Kristian Hveem, Licia Iacoviello, M Kamran Ikram, Vilma Irazola, Modou Jobe, Pekka Jousilahti, Pontiano Kaleebu, Maryam Kavousi, Frank Kee, Davood Khalili, Wolfgang Koenig, Anna Kontsevaya, Kari Kuulasmaa, Karl J Lackner, David M Leistner, Lars Lind, Allan Linneberg, Thiess Lorenz, Magnus Nakrem Lyngbakken, Reza Malekzadeh, Sofia Malyutina, Ellisiv B Mathiesen, Olle Melander, Andres Metspalu, J Jaime Miranda, Marie Moitry, Joseph Mugisha, Mahdi Nalini, Vijay Nambi, Toshiharu Ninomiya, Karen Oppermann, Eleonora D'Orsi, Andrzej Pająk, Luigi Palmieri, Demosthenes Panagiotakos, Arokiasamy Perianayagam, Annette Peters, Hossein Poustchi, Andrew M Prentice, Eva Prescott, Ulf Risérus, Veikko Salomaa, Susana Sans, Satoko Sakata, Ben Schöttker, Aletta E Schutte, Sadaf G Sepanlou, Sanjib Kumar Sharma, Jonathan E Shaw, Leon A Simons, Stefan Söderberg, Abdonas Tamosiunas, Barbara Thorand, Hugh Tunstall-Pedoe, Raphael Twerenbold, Diego Vanuzzo, Giovanni Veronesi, Julia Waibel, S Goya Wannamethee, Masafumi Watanabe, Philipp S Wild, Yao Yao, Yi Zeng, Andreas Ziegler, Stefan Blankenberg

Faculty, Staff and Students Publications

BACKGROUND: Five modifiable risk factors are associated with cardiovascular disease (CVD) and all-cause mortality. The regional and sex-specific prevalence of these modifiable risk factors and their impact on CVD and all-cause mortality have not been evaluated using individual-level data.

METHODS: The Global Cardiovascular Risk Consortium harmonized individual-level data from 112 cohort studies conducted in 34 countries and 8 geographic regions. Associations between body-mass index, systolic blood pressure, non-high-density lipoprotein cholesterol, smoking, and diabetes with incident CVD and all-cause mortality were examined using Cox regression analyses and stratified by geographic region, age and sex. Population-attributable fractions were estimated for 10-year incident …

Spa-Stocsy: An Automated Tool For Identifying Annotated And Non-Annotated Metabolites In High-Throughput Nmr Spectra, Xu Han, Wanli Wang, Li-Hua Ma, Ismael Ai-Ramahi, Juan Botas, Kevin Mackenzie, Genevera I Allen, Damian W Young, Zhandong Liu, Mirjana Maletic-Savatic

Faculty, Staff and Students Publications

MOTIVATION: Nuclear magnetic resonance spectroscopy (NMR) is widely used to analyze metabolites in biological samples, but the analysis requires specific expertise, it is time-consuming, and can be inaccurate. Here, we present a powerful automate tool, SPatial clustering Algorithm-Statistical TOtal Correlation SpectroscopY (SPA-STOCSY), which overcomes challenges faced when analyzing NMR data and identifies metabolites in a sample with high accuracy.

RESULTS: As a data-driven method, SPA-STOCSY estimates all parameters from the input dataset. It first investigates the covariance pattern among datapoints and then calculates the optimal threshold with which to cluster datapoints belonging to the same structural unit, i.e. the metabolite. …

Scribbledom: Using Scribble-Annotated Histology Images To Identify Domains In Spatial Transcriptomics Data, Mohammad Nuwaisir Rahman, Abdullah Al Noman, Abir Mohammad Turza, Mohammed Abid Abrar, Md Abul Hassan Samee, M Saifur Rahman

Faculty, Staff and Students Publications

Motivation

Spatial domain identification is a very important problem in the field of spatial transcriptomics. The state-of-the-art solutions to this problem focus on unsupervised methods, as there is lack of data for a supervised learning formulation. The results obtained from these methods highlight significant opportunities for improvement.

Results

In this article, we propose a potential avenue for enhancement through the development of a semi-supervised convolutional neural network based approach. Named “ScribbleDom”, our method leverages human expert’s input as a form of semi-supervision, thereby seamlessly combines the cognitive abilities of human experts with the computational power of machines. ScribbleDom incorporates a …

Heterocyclic Merging Of Stereochemically Diverse Chiral Piperazines And Morpholines With Indazoles, Amol B Viveki, Timothy M Mansfield, Kevin A Tran, Evan Lenkeit, Kevin R Mackenzie, Damian W Young, Srinivas Chamakuri

Faculty, Staff and Students Publications

We report a heterocyclic merging approach to construct novel indazolo-piperazines and indazolo-morpholines. Starting from chiral diamines and amino alcohols, novel regiochemically (1,3 and 1,4) and stereochemically diverse (relative and absolute) cohorts of indazolo-piperazines and indazolo-morpholines were obtained within six or seven steps. The key transformations involved are a Smiles rearrangement to generate the indazole core structure and a late-stage Michael addition to build the piperazine and morpholine heterocycles. We further explored additional vector diversity by incorporating substitutions on the indazole aromatic ring, generating a total of 20 unique, enantiomerically pure heterocyclic scaffolds.

Chronic Kidney Disease Promotes Atrial Fibrillation Via Inflammasome Pathway Activation, Jia Song, Jose Alberto Navarro-Garcia, Jiao Wu, Arnela Saljic, Issam Abu-Taha, Luge Li, Satadru K Lahiri, Joshua A Keefe, Yuriana Aguilar-Sanchez, Oliver M Moore, Yue Yuan, Xiaolei Wang, Markus Kamler, William E Mitch, Gema Ruiz-Hurtado, Zhaoyong Hu, Sandhya S Thomas, Dobromir Dobrev, Xander Ht Wehrens, Na Li

Faculty, Staff and Students Publications

Chronic kidney disease (CKD) is associated with a higher risk of atrial fibrillation (AF). The mechanistic link between CKD and AF remains elusive. IL-1β, a main effector of NLR family pyrin domain-containing 3 (NLRP3) inflammasome activation, is a key modulator of conditions associated with inflammation, such as AF and CKD. Circulating IL-1β levels were elevated in patients with CKD who had AF (versus patients with CKD in sinus rhythm). Moreover, NLRP3 activity was enhanced in atria of patients with CKD. To elucidate the role of NLRP3/IL-1β signaling in the pathogenesis of CKD-induced AF, Nlrp3-/- and WT mice were subjected to …

Kinome Reprogramming Is A Targetable Vulnerability In Esr1 Fusion-Driven Breast Cancer, Xuxu Gou, Beom-Jun Kim, Meenakshi Anurag, Jonathan T Lei, Meggie N Young, Matthew V Holt, Diana Fandino, Craig T Vollert, Purba Singh, Mohammad A Alzubi, Anna Malovannaya, Lacey E Dobrolecki, Michael T Lewis, Shunqiang Li, Charles E Foulds, Matthew J Ellis

Faculty, Staff and Students Publications

Transcriptionally active ESR1 fusions (ESR1-TAF) are a potent cause of breast cancer endocrine therapy (ET) resistance. ESR1-TAFs are not directly druggable because the C-terminal estrogen/anti-estrogen-binding domain is replaced with translocated in-frame partner gene sequences that confer constitutive transactivation. To discover alternative treatments, a mass spectrometry (MS)-based kinase inhibitor pulldown assay (KIPA) was deployed to identify druggable kinases that are upregulated by diverse ESR1-TAFs. Subsequent explorations of drug sensitivity validated RET kinase as a common therapeutic vulnerability despite remarkable ESR1-TAF C-terminal sequence and structural diversity. Organoids and xenografts from a pan-ET-resistant patient-derived xenograft model that harbors the ESR1-e6>YAP1 TAF were …

Type 1 Diabetes Genetic Risk Score Differentiates Subgroups Of Ketosis-Prone Diabetes, Deborah Osafehinti, Surya N Mulukutla, Christiane S Hampe, Ruchi Gaba, Nalini Ram, Michael N Weedon, Richard A Oram, Ashok Balasubramanyam

Faculty, Staff and Students Publications

OBJECTIVE: To determine whether genetic risk for type 1 diabetes (T1D) differentiates the four Aβ subgroups of ketosis-prone diabetes (KPD), where A+ and A- define the presence or absence of islet autoantibodies and β+ and β- define the presence or absence of β-cell function.

RESEARCH DESIGN AND METHODS: We compared T1D genetic risk scores (GRS) of patients with KPD across subgroups, race/ethnicity, β-cell function, and glycemia.

RESULTS: Among 426 patients with KPD (54% Hispanic, 31% African American, 11% White), rank order of GRS was A+β- > A+β+ = A-β- > A-β+. GRS of A+β- KPD was lower than that of a T1D …

Vadadustat For Treatment Of Anemia In Patients With Dialysis-Dependent Chronic Kidney Disease Receiving Peritoneal Dialysis, Mark J Sarnak, Rajiv Agarwal, Neil Boudville, Pradip C P Chowdhury, Kai-Uwe Eckardt, Carlos R Gonzalez, Laura A Kooienga, Mark J Koury, Kwabena A Ntoso, Wenli Luo, Patrick S Parfrey, Dennis L Vargo, Wolfgang C Winkelmayer, Zhiqun Zhang, Glenn M Chertow

Faculty, Staff and Students Publications

BACKGROUND: Hypoxia-inducible factor prolyl hydroxylase inhibitors such as vadadustat may provide an oral alternative to injectable erythropoiesis-stimulating agents for treating anemia in patients receiving peritoneal dialysis. In two randomized (1:1), global, phase 3, open-label, sponsor-blind, parallel-group, active-controlled noninferiority trials in patients with dialysis-dependent chronic kidney disease (INNO2VATE), vadadustat was noninferior to darbepoetin alfa with respect to cardiovascular safety and hematological efficacy. Vadadustat's effects in patients receiving only peritoneal dialysis is unclear.

METHODS: We conducted a post hoc analysis of patients in the INNO2VATE trials receiving peritoneal dialysis at baseline. The prespecified primary safety endpoint was time to first major cardiovascular …

Hiv-1 Vpu Protein Forms Stable Oligomers In Aqueous Solution Via Its Transmembrane Domain Self-Association, Saman Majeed, Lan Dang, Md Majharul Islam, Olamide Ishola, Peter P Borbat, Steven J Ludtke, Elka R Georgieva

Faculty, Staff and Students Publications

We report our findings on the assembly of the HIV-1 protein Vpu into soluble oligomers. Vpu is a key HIV-1 protein. It has been considered exclusively a single-pass membrane protein. Previous observations show that this protein forms stable oligomers in aqueous solution, but details about these oligomers still remain obscure. This is an interesting and rather unique observation, as the number of proteins transitioning between soluble and membrane embedded states is limited. In this study we made use of protein engineering, size exclusion chromatography, cryoEM and electron paramagnetic resonance (EPR) spectroscopy to better elucidate the nature of the soluble oligomers. …

A Novel Grk3-Hdac2 Regulatory Pathway Is A Key Direct Link Between Neuroendocrine Differentiation And Angiogenesis In Prostate Cancer Progression, Samira Naderinezhad, Guoliang Zhang, Zheng Wang, Dayong Zheng, Mohit Hulsurkar, Michael Bakhoum, Ning Su, Han Yang, Tao Shen, Wenliang Li

Faculty, Staff and Students Publications

The mechanisms underlying the progression of prostate cancer (PCa) to neuroendocrine prostate cancer (NEPC), an aggressive PCa variant, are largely unclear. Two prominent NEPC phenotypes are elevated NE marker expression and heightened angiogenesis. Identifying the still elusive direct molecular links connecting angiogenesis and neuroendocrine differentiation (NED) is crucial for our understanding and targeting of NEPC. Here we found that histone deacetylase 2 (HDAC2), whose role in NEPC has not been reported, is one of the most upregulated epigenetic regulators in NEPC. HDAC2 promotes both NED and angiogenesis. G protein-coupled receptor kinase 3 (GRK3), also upregulated in NEPC, is a critical …

Nurse Leader Perceptions Of Data In The Veterans Health Administration: A Qualitative Evaluation, Janine J Wong, Richard P Sorelle, Christine Yang, Melissa K Knox, Sylvia J Hysong, Lynette E Dorsey, Patrick N O'Mahen, Laura A Petersen

Faculty, Staff and Students Publications

Healthcare systems and nursing leaders aim to make evidence-based nurse staffing decisions. Understanding how nurses use and perceive available data to support safe staffing can strengthen learning healthcare systems and support evidence-based practice, particularly given emerging data availability and specific nursing challenges in data usability. However, current literature offers sparse insight into the nature of data use and challenges in the inpatient nurse staffing management context. We aimed to investigate how nurse leaders experience using data to guide their inpatient staffing management decisions in the Veterans Health Administration, the largest integrated healthcare system in the United States. We conducted semistructured …

Oral Delivery Of Rnai For Cancer Therapy, Humayra Afrin, Renu Geetha Bai, Raj Kumar, Sheikh Shafin Ahmad, Sandeep K Agarwal, Md Nurunnabi

Faculty, Staff and Students Publications

Cancer is a major health concern worldwide and is still in a continuous surge of seeking for effective treatments. Since the discovery of RNAi and their mechanism of action, it has shown promises in targeted therapy for various diseases including cancer. The ability of RNAi to selectively silence the carcinogenic gene makes them ideal as cancer therapeutics. Oral delivery is the ideal route of administration of drug administration because of its patients' compliance and convenience. However, orally administered RNAi, for instance, siRNA, must cross various extracellular and intracellular biological barriers before it reaches the site of action. It is very …

Factors Influencing Prescribing The First Add-On Disease-Modifying Antirheumatic Drugs In Patients Initiating Methotrexate For Rheumatoid Arthritis, Yinan Huang, Satabdi Chatterjee, Sandeep K Agarwal, Hua Chen, Michael L Johnson, Rajender R Aparasu

Faculty, Staff and Students Publications

BACKGROUND: Advances in Disease-Modifying Antirheumatic Drugs (DMARDs) have expanded the treatment landscape for Rheumatoid Arthritis (RA). Guidelines recommend adding either conventional synthetic (cs), biologic (b), or targeted synthetic (ts) DMARDs to methotrexate (MTX) for managing RA. Limited evidence exists regarding the factors that contribute to adding a DMARD agent to the MTX regimen. This study examined the factors associated with adding the first DMARD in RA patients initiating MTX.

METHODS: This retrospective cohort study utilized the MarketScan data (2012-2014) involving adults (aged ≥18) with RA initiating an MTX (index date) between Jul 1, 2012 and Dec 30, 2013, and with …

The Transcription Factor Chrebp Links Mitochondrial Lipidomes To Mitochondrial Morphology And Progression Of Diabetic Kidney Disease, Li Li, Jianyin Long, Koki Mise, Naravat Poungavrin, Philip L Lorenzi, Iqbal Mahmud, Lin Tan, Pradip K Saha, Yashpal S Kanwar, Benny H Chang, Farhad R Danesh

Faculty, Staff and Students Publications

A substantial body of evidence has established the contributions of both mitochondrial dynamics and lipid metabolism to the pathogenesis of diabetic kidney disease (DKD). However, the precise interplay between these two key metabolic regulators of DKD is not fully understood. Here, we uncover a link between mitochondrial dynamics and lipid metabolism by investigating the role of carbohydrate-response element-binding protein (ChREBP), a glucose-responsive transcription factor and a master regulator of lipogenesis, in kidney podocytes. We find that inducible podocyte-specific knockdown of ChREBP in diabetic db/db mice improves key biochemical and histological features of DKD in addition to significantly reducing mitochondrial fragmentation. …

Structures Of The Insecticidal Toxin Complex Subunit Xpta2 Highlight Roles For Flexible Domains, Cole L Martin, David W Chester, Christopher D Radka, Lurong Pan, Zhengrong Yang, Rachel C Hart, Elad M Binshtein, Zhao Wang, Lisa Nagy, Lawrence J Delucas, Stephen G Aller

Faculty, Staff and Students Publications

The Toxin Complex (Tc) superfamily consists of toxin translocases that contribute to the targeting, delivery, and cytotoxicity of certain pathogenic Gram-negative bacteria. Membrane receptor targeting is driven by the A-subunit (TcA), which comprises IgG-like receptor binding domains (RBDs) at the surface. To better understand XptA2, an insect specific TcA secreted by the symbiont

Early Detection Of Lung Cancer Using Artificial Intelligence-Enhanced Optical Nanosensing Of Chromatin Alterations In Field Carcinogenesis, Ali Daneshkhah, Sravya Prabhala, Parvathi Viswanathan, Hariharan Subramanian, Jianan Lin, Andrew S Chang, Ankit Bharat, Hemant Kumar Roy, Vadim Backman

Faculty, Staff and Students Publications

Supranucleosomal chromatin structure, including chromatin domain conformation, is involved in the regulation of gene expression and its dysregulation has been associated with carcinogenesis. Prior studies have shown that cells in the buccal mucosa carry a molecular signature of lung cancer among the cigarette-smoking population, the phenomenon known as field carcinogenesis or field of injury. Thus, we hypothesized that chromatin structural changes in buccal mucosa can be predictive of lung cancer. However, the small size of the chromatin chain (approximately 20 nm) folded into chromatin packing domains, themselves typically below 300 nm in diameter, preclude the detection of alterations in intradomain …

Clinical Predictors And Outcomes After Left Ventricular Assist Device Implantation And Tracheostomy, Harveen K Lamba, Lucy D Hart, Qianzi Zhang, Jackquelin M Loera, Andrew B Civitello, Ajith P Nair, Mourad H Senussi, Gabriel Loor, Kenneth K Liao, Alexis E Shafii, Subhasis Chatterjee

Faculty, Staff and Students Publications

BACKGROUND: Postoperative respiratory failure is a major complication that affects up to 10% of patients who undergo cardiac surgery and has a high in-hospital mortality rate. Few studies have investigated whether patients who require tracheostomy for postoperative respiratory failure after continuous-flow left ventricular assist device (CF-LVAD) implantation have worse survival outcomes than patients who do not.

OBJECTIVE: To identify risk factors for respiratory failure necessitating tracheostomy in CF-LVAD recipients and to compare survival outcomes between those who did and did not require tracheostomy.

METHODS: Consecutive patients who underwent primary CF-LVAD placement at a single institution between August 1, 2002, and …

A Defective Mechanosensing Pathway Affects Fibroblast-To-Myofibroblast Transition In The Old Male Mouse Heart, Aude Angelini, Joann Trial, Alexander B Saltzman, Anna Malovannaya, Katarzyna A Cieslik

Faculty, Staff and Students Publications

The cardiac fibroblast interacts with an extracellular matrix (ECM), enabling myofibroblast maturation via a process called mechanosensing. Although in the aging male heart, ECM is stiffer than in the young mouse, myofibroblast development is impaired, as demonstrated in 2-D and 3-D experiments. In old male cardiac fibroblasts, we found a decrease in actin polymerization, α-smooth muscle actin (α-SMA), and Kindlin-2 expressions, the latter an effector of the mechanosensing. When Kindlin-2 levels were manipulated via siRNA interference, young fibroblasts developed an old-like fibroblast phenotype, whereas Kindlin-2 overexpression in old fibroblasts reversed the defective phenotype. Finally, inhibition of overactivated extracellular regulated kinases …

Oleoylethanolamide Facilitates Pparα And Tfeb Signaling And Attenuates Aβ Pathology In A Mouse Model Of Alzheimer’S Disease, Michele M Comerota, Manasee Gedam, Wen Xiong, Feng Jin, Lisheng Deng, Meng C Wang, Jin Wang, Hui Zheng

Faculty, Staff and Students Publications

BACKGROUND: Age is the strongest risk factor for the development of Alzheimer's disease (AD). Besides the pathological hallmarks of β-amyloid (Aβ) plaques and neurofibrillary tangles, emerging evidence demonstrates a critical role of microglia and neuroinflammation in AD pathogenesis. Oleoylethanolamide (OEA) is an endogenous lipid amide that has been shown to promote lifespan and healthspan in C. elegans through regulation of lysosome-to-nucleus signaling and cellular metabolism. The goal of our study was to determine the role of OEA in the mediation of microglial activity and AD pathology using its stable analog, KDS-5104.

METHODS: We used primary microglial cultures and genetic and …

Spatial Organization Of The Mouse Retina At Single Cell Resolution By Merfish, Jongsu Choi, Jin Li, Salma Ferdous, Qingnan Liang, Jeffrey R Moffitt, Rui Chen

Faculty, Staff and Students Publications

The visual signal processing in the retina requires the precise organization of diverse neuronal types working in concert. While single-cell omics studies have identified more than 120 different neuronal subtypes in the mouse retina, little is known about their spatial organization. Here, we generated the single-cell spatial atlas of the mouse retina using multiplexed error-robust fluorescence in situ hybridization (MERFISH). We profiled over 390,000 cells and identified all major cell types and nearly all subtypes through the integration with reference single-cell RNA sequencing (scRNA-seq) data. Our spatial atlas allowed simultaneous examination of nearly all cell subtypes in the retina, revealing …

Structural Underpinnings Of Mutation Rate Variations In The Human Genome, Zian Liu, Md Abul Hassan Samee

Faculty, Staff and Students Publications

Single nucleotide mutation rates have critical implications for human evolution and genetic diseases. Importantly, the rates vary substantially across the genome and the principles underlying such variations remain poorly understood. A recent model explained much of this variation by considering higher-order nucleotide interactions in the 7-mer sequence context around mutated nucleotides. This model's success implicates a connection between DNA shape and mutation rates. DNA shape, i.e. structural properties like helical twist and tilt, is known to capture interactions between nucleotides within a local context. Thus, we hypothesized that changes in DNA shape features at and around mutated positions can explain …

Dna-Encoded Chemical Libraries Yield Non-Covalent And Non-Peptidic Sars-Cov-2 Main Protease Inhibitors, Ravikumar Jimmidi, Srinivas Chamakuri, Shuo Lu, Melek Nihan Ucisik, Peng-Jen Chen, Kurt M Bohren, Seyed Arad Moghadasi, Leroy Versteeg, Christina Nnabuife, Jian-Yuan Li, Xuan Qin, Ying-Chu Chen, John C Faver, Pranavanand Nyshadham, Kiran L Sharma, Banumathi Sankaran, Allison Judge, Zhifeng Yu, Feng Li, Jeroen Pollet, Reuben S Harris, Martin M Matzuk, Timothy Palzkill, Damian W Young

Faculty, Staff and Students Publications

The development of SARS-CoV-2 main protease (Mpro) inhibitors for the treatment of COVID-19 has mostly benefitted from X-ray structures and preexisting knowledge of inhibitors; however, an efficient method to generate Mpro inhibitors, which circumvents such information would be advantageous. As an alternative approach, we show here that DNA-encoded chemistry technology (DEC-Tec) can be used to discover inhibitors of Mpro. An affinity selection of a 4-billion-membered DNA-encoded chemical library (DECL) using Mpro as bait produces novel non-covalent and non-peptide-based small molecule inhibitors of Mpro with low nanomolar Ki values. Furthermore, these compounds demonstrate efficacy against mutant forms of Mpro that …

Noncanonical Binding Of Transcription Factors: Time To Revisit Specificity?, Md Abul Hassan Samee

Faculty, Staff and Students Publications

Transcription factors (TFs) are one of the most studied classes of DNA-binding proteins that have a direct functional impact on gene transcription and thus, on human physiology and disease. The mechanisms that TFs use for recognizing target DNA binding sites have been studied for nearly five decades, yet they remain poorly understood. It is classically assumed that a TF recognizes a specific sequence pattern, or motif, as its binding sites. However, recent studies are consistently finding examples of noncanonical binding, that is, TFs binding at sites that do not resemble their sequence motifs. Here we review the current literature on …

Disparities In Antifibrotic Medication Utilization Among Veterans With Idiopathic Pulmonary Fibrosis, Bhavika Kaul, Joyce S Lee, Laura A Petersen, Charles Mcculloch, Ivan O Rosas, Venkata D Bandi, Ning Zhang, Alison M Dedent, Harold R Collard, Mary A Whooley

Faculty, Staff and Students Publications

BACKGROUND: Two antifibrotic medications, pirfenidone and nintedanib, are approved for the treatment of idiopathic pulmonary fibrosis (IPF). Little is known about their real-world adoption.

RESEARCH QUESTION: What are the real-world antifibrotic utilization rates and factors associated with uptake among a national cohort of veterans with IPF?

STUDY DESIGN AND METHODS: This study identified veterans with IPF who received care either provided by the Veterans Affairs (VA) Healthcare System or non-VA care paid for by the VA. Patients who had filled at least one antifibrotic prescription through the VA pharmacy or Medicare Part D between October 15, 2014, and December 31, …

Kinase Inhibitor Pulldown Assay Identifies A Chemotherapy Response Signature In Triple-Negative Breast Cancer Based On Purine-Binding Proteins, Junkai Wang, Alexander B Saltzman, Eric J Jaehnig, Jonathan T Lei, Anna Malovannaya, Matthew V Holt, Meggie N Young, Mothaffar F Rimawi, Foluso O Ademuyiwa, Meenakshi Anurag, Beom-Jun Kim, Matthew J Ellis

Faculty, Staff and Students Publications

Triple-negative breast cancer (TNBC) constitutes 10%–15% of all breast tumors. The current standard of care is multiagent chemotherapy, which is effective in only a subset of patients. The original objective of this study was to deploy a mass spectrometry (MS)-based kinase inhibitor pulldown assay (KIPA) to identify kinases elevated in non-pCR (pathologic complete response) cases for therapeutic targeting. Frozen optimal cutting temperature compound–embedded core needle biopsies were obtained from 43 patients with TNBC before docetaxel- and carboplatin-based neoadjuvant chemotherapy. KIPA was applied to the native tumor lysates that were extracted from samples with high tumor content. Seven percent of all …

Acute Manipulation Of Erna Level For Dissecting Its Roles In Transcriptional Regulation, Lanxin Bei

Dissertations and Theses (Open Access)

Enhancers are the central genetic elements controlling cell-type and state specific transcription programs to dictate cell fates during development. Mechanistic understanding of enhancer action is important for both biology and disease research. In the human genome, more than 60k human enhancers were found to produce non-coding transcripts named enhancer RNAs (eRNAs). These created a new challenge to understand enhancer functions, which now are not only DNA elements that promote transcription but also RNA-producing transcription units themselves. Importantly, deregulation of eRNAs was associated with various diseases such as cancer, immune disorders, and neurodegeneration. However, the direct role of eRNAs in transcriptional …

Study Of Polytopic Membrane Protein Topological Organization As A Function Of Membrane Lipid Composition, Takefumi Morizumi, Kyumhyuk Kim, Hai Li, Elena G Govorunova, Oleg A Sineshchekov, Yumei Wang, Lei Zheng, Éva Bertalan, Ana-Nicoleta Bondar, Azam Askari, Leonid S Brown, John L Spudich, Oliver P Ernst

Faculty, Staff and Student Publications

Kalium channelrhodopsin 1 from Hyphochytrium catenoides (HcKCR1) is a light-gated channel used for optogenetic silencing of mammalian neurons. It selects K+ over Na+ in the absence of the canonical tetrameric K+ selectivity filter found universally in voltage- and ligand-gated channels. The genome of H. catenoides also encodes a highly homologous cation channelrhodopsin (HcCCR), a Na+ channel with >100-fold larger Na+ to K+ permeability ratio. Here, we use cryo-electron microscopy to determine atomic structures of these two channels embedded in peptidiscs to elucidate structural foundations of their dramatically different cation selectivity. Together with structure-guided mutagenesis, we show that K+ versus Na+ …