Biochemistry, Biophysics, and Structural Biology Commons^™

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 …

Co-Targeting Nucleus Accumbens Associate 1 And Nf-Κb Signaling Synergistically Inhibits Melanoma Growth, Lixiang Gu, Xingcong Ren, Chrispus Ngule, Xiaofang Xiong, Jianxun Song, Zhiguo Li, Jin-Ming Yang

Markey Cancer Center Faculty Publications

Nucleus-accumbens-associated protein-1 (NAC1) is a cancer-related transcriptional factor encoded by the NACC1 gene, which is amplified and overexpressed in various human cancers and has been appreciated as one of the top potential cancer driver genes. NAC1 has therefore been explored as a potential therapeutic target for managing malignant tumors. Here, we show that NAC1 is a negative regulator of NF-κB signaling, and NAC1 depletion enhances the level of the nuclear NF-κB in human melanoma. Furthermore, the inhibition of NF-κB signaling significantly potentiates the antineoplastic activity of the NAC1 inhibition in both the cultured melanoma cells and xenograft tumors. This study …

Metabolic Disruption Induced By Mtor Signaling Pathway Inhibition In Regulatory T-Cell Expansion For Clinical Application, Roberto Gedaly, Gabriel Orozco, Alexandre P. Ancheta, Mackenzie Donoho, Siddharth Desai, Fanny Chapelin, Aman Khurana, Lillie J. Lewis, Cuiping Zhang, Francesc Marti

Markey Cancer Center Faculty Publications

Background: Regulatory T cell (Treg) therapy is considered an alternative approach to induce tolerance in transplantation. If successful, this therapy may have implications on immunosuppression minimization/withdrawal to reduce drug-induced toxicity in patients. The aim of this study was to assess the efficacy of the mTORC1/C2 inhibitor, AZD8055, in the manufacturing of clinically competent Treg cells and compare the effects with those induced by rapamycin (RAPA), another mTOR inhibitor commonly used in Treg expansion protocols.

Methods: Primary human Treg cells were isolated from leukapheresis product. Cell viability, expansion rates, suppressive function, autophagy, mitochondrial unfolded protein response (mitoUPR), and cell metabolic profile …

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

Markey Cancer Center Faculty 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 X. nematophilus from the intestine of entomopathogenic nematodes, we determined structures by X-ray crystallography and cryo-EM. Contrary to a previous report, XptA2 is pentameric. RBD-B exhibits an indentation from crystal packing that indicates loose association with the shell and a hotspot for possible receptor binding or a …

The S1p Receptor 1 Antagonist Ponesimod Reduces Tlr4-Induced Neuroinflammation And Increases Aβ Clearance In 5xfad Mice, Zhihui Zhu, Liping Zhang, Ahmed Elsherbini, Simone M. Crivelli, Priyanka Tripathi, Carmen Harper, Zainuddin Quadri, Stefka D. Spassieva, Erhard Bieberich

Markey Cancer Center Faculty Publications

Background Previously, we showed that the sphingosine-1-phosphate (S1P) transporter spinster 2 (Spns2) mediates activation of microglia in response to amyloid β peptide (Aβ). Here, we investigated if Ponesimod, a functional S1P receptor 1 (S1PR1) antagonist, prevents Aβ-induced activation of glial cells and Alzheimer’s disease (AD) pathology.

Methods We used primary cultures of glial cells and the 5XFAD mouse model to determine the effect of Aβ and Ponesimod on glial activation, Aβ phagocytosis, cytokine levels and pro-inflammatory signaling pathways, AD pathology, and cognitive performance.

Findings Aβ42 increased the levels of TLR4 and S1PR1, leading to their complex formation. Ponesimod prevented the …

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 …

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 …

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, …

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+ …

Dual Antiplatelet Therapy: A Concise Review For Clinicians, Hafeez Ul Hassan Virk, Johao Escobar, Mario Rodriguez, Eric R Bates, Umair Khalid, Hani Jneid, Yochai Birnbaum, Glenn N Levine, Sidney C Smith, Chayakrit Krittanawong

Faculty, Staff and Students Publications

Dual antiplatelet therapy (DAPT) combines two antiplatelet agents to decrease the risk of thrombotic complications associated with atherosclerotic cardiovascular diseases. Emerging data about the duration of DAPT is being published continuously. New approaches are trying to balance the time, benefits, and risks for patients taking DAPT for established cardiovascular diseases. Short-term dual DAPT of 3-6 months, or even 1 month in high-bleeding risk patients, is equivalent in terms of efficacy and effectiveness compared to long-term DAPT for patients who experienced percutaneous coronary intervention in an acute coronary syndrome setting. Prolonged DAPT beyond 12 months reduces stent thrombosis, major adverse cardiovascular …

Molecular Dissection And Testing Of Prss37 Function Through Lc-Ms/Ms And The Generation Of A Prss37 Humanized Mouse Model, Courtney Sutton, Kaori Nozawa, Katarzyna Kent, Alexander Saltzman, Mei Leng, Sureshbabu Nagarajan, Anna Malovannaya, Masahito Ikawa, Thomas X Garcia, Martin M Matzuk

Faculty, Staff and Students Publications

The quest for a non-hormonal male contraceptive pill for men still exists. Serine protease 37 (PRSS37) is a sperm-specific protein that when ablated in mice renders them sterile. In this study we sought to examine the molecular sequelae of PRSS37 loss to better understand its molecular function, and to determine whether human PRSS37 could rescue the sterility phenotype of knockout (KO) mice, allowing for a more appropriate model for drug molecule testing. To this end, we used CRISPR-EZ to create mice lacking the entire coding region of Prss37, used pronuclear injection to create transgenic mice expressing human PRSS37, intercrossed these …

Circadian Disruption And Colorectal Cancer Incidence In Black Women, Lauren E Barber, Trang Vopham, Laura F White, Hemant K Roy, Julie R Palmer, Kimberly A Bertrand

Faculty, Staff and Students Publications

BACKGROUND: Animal and experimental studies suggest circadian disruption increases colorectal cancer risk, but evidence in humans is limited. We examined night shift work, chronotype, and residential position within a time zone, proxies for circadian disruption, in relation to colorectal cancer risk.

METHODS: Participants in the Black Women's Health Study, a prospective cohort of 59,000 Black American women established in 1995, reported history of night shift work and chronotype on follow-up questionnaires. Residential position within a time zone was estimated using participant addresses at each questionnaire cycle. Number of colorectal cancer cases and follow-up duration varied by analysis depending on timing …

Tiam1 Coordinates Synaptic Structural And Functional Plasticity Underpinning The Pathophysiology Of Neuropathic Pain, Lingyong Li, Qin Ru, Yungang Lu, Xing Fang, Guanxing Chen, Ali Bin Saifullah, Changqun Yao, Kimberley F Tolias

Faculty, Staff and Students Publications

Neuropathic pain is a common, debilitating chronic pain condition caused by damage or a disease affecting the somatosensory nervous system. Understanding the pathophysiological mechanisms underlying neuropathic pain is critical for developing new therapeutic strategies to treat chronic pain effectively. Tiam1 is a Rac1 guanine nucleotide exchange factor (GEF) that promotes dendritic and synaptic growth during hippocampal development by inducing actin cytoskeletal remodeling. Here, using multiple neuropathic pain animal models, we show that Tiam1 coordinates synaptic structural and functional plasticity in the spinal dorsal horn via actin cytoskeleton reorganization and synaptic NMDAR stabilization and that these actions are essential for the …

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Circular Rna As Therapeutic Targets In Atherosclerosis: Are We Running In Circles?, Jeffrey Triska, Christo Mathew, Yang Zhao, Yuqing E Chen, Yochai Birnbaum

Faculty, Staff and Students Publications

Much attention has been paid lately to harnessing the diagnostic and therapeutic potential of non-coding circular ribonucleic acids (circRNAs) and micro-RNAs (miRNAs) for the prevention and treatment of cardiovascular diseases. The genetic environment that contributes to atherosclerosis pathophysiology is immensely complex. Any potential therapeutic application of circRNAs must be assessed for risks, benefits, and off-target effects in both the short and long term. A search of the online PubMed database for publications related to circRNA and atherosclerosis from 2016 to 2022 was conducted. These studies were reviewed for their design, including methods for developing atherosclerosis and the effects of the …

Enhanced Bypass Of Pd-L1 Translation Reduces The Therapeutic Response To Mtor Kinase Inhibitors, Yanan Cao, Qing Ye, Murong Ma, Qing-Bai She

Markey Cancer Center Faculty Publications

Increased PD-L1 expression in cancer cells is known to enhance immunosuppression, but the mechanism underlying PD-L1 upregulation is incompletely characterized. We show that PD-L1 expression is upregulated through internal ribosomal entry site (IRES)-mediated translation upon mTORC1 inhibition. We identify an IRES element in the PD-L1 50-UTR that permits cap-independent translation and promotes continuous production of PD-L1 protein despite effective inhibition of mTORC1. eIF4A is found to be a key PD-L1 IRES-binding protein that enhances PD-L1 IRES activity and protein production in tumor cells treated with mTOR kinase inhibitors (mTORkis). Notably, treatment with mTORkis in vivo elevates PD-L1 levels and reduces …

Messes: Software For Transforming Messy Research Datasets Into Clean Submissions To Metabolomics Workbench For Public Sharing, P. Travis Thompson, Hunter N. B. Moseley

Markey Cancer Center Faculty Publications

In recent years, the FAIR guiding principles and the broader concept of open science has grown in importance in academic research, especially as funding entities have aggressively promoted public sharing of research products. Key to public research sharing is deposition of datasets into online data repositories, but it can be a chore to transform messy unstructured data into the forms required by these repositories. To help generate Metabolomics Workbench depositions, we have developed the MESSES (Metadata from Experimental SpreadSheets Extraction System) software package, implemented in the Python 3 programming language and supported on Linux, Windows, and Mac operating systems. MESSES …

The Metabolomics Workbench File Status Website: A Metadata Repository Promoting Fair Principles Of Metabolomics Data, Christian D. Powell, Hunter N. B. Moseley

Markey Cancer Center Faculty Publications

Background: An updated version of the mwtab Python package for programmatic access to the Metabolomics Workbench (MetabolomicsWB) data repository was released at the beginning of 2021. Along with updating the package to match the changes to MetabolomicsWB’s ‘mwTab’ file format specification and enhancing the package’s functionality, the included validation facilities were used to detect and catalog file inconsistencies and errors across all publicly available datasets in MetabolomicsWB.

Results: The MetabolomicsWB File Status website was developed to provide continuous validation of MetabolomicsWB data files and a useful interface to all found inconsistencies and errors. This list of detectable issues/errors include format …

Characterization Of Atrial And Ventricular Remodeling In An Improved Minimally Invasive Mouse Model Of Transverse Aortic Constriction, Jose Alberto Navarro-Garcia, Satadru K Lahiri, Yuriana Aguilar-Sanchez, Anilkumar K Reddy, Xander H T Wehrens

Faculty, Staff and Students Publications

INTRODUCTION: Heart failure (HF) is the leading cause of death worldwide. Most large and small animal disease models of HF are based on surgical procedures. A common surgical technique to induce HF is transverse aortic constriction (TAC), which induces pressure overload. The conventional TAC (cTAC) procedure is a highly invasive surgery that is associated with severe inflammation and excessive perioperative deaths.

AIM: To establish an improved, minimally invasive TAC (mTAC) procedure that does not require thoracotomy.

METHODS AND RESULTS: Following anesthesia, mice were intubated, and a small incision was made at the neck and chest. After cutting the sternum about …

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 …

Suitability Of Double-Stranded Dna As A Molecular Standard For The Validation Of Analytical Ultracentrifugation Instruments, Maduni Ranasinghe, Jonathan M Fogg, Daniel J Catanese, Lynn Zechiedrich, Borries Demeler

Faculty, Staff and Students Publications

To address the current lack of validated molecular standards for analytical ultracentrifugation (AUC), we investigated the suitability of double-stranded DNA molecules. We compared the hydrodynamic properties of linear and circular DNA as a function of temperature. Negatively supercoiled, nicked, and linearized 333 and 339 bp minicircles were studied. We quantified the hydrodynamic properties of these DNAs at five different temperatures, ranging from 4 to 37 °C. To enhance the precision of our measurements, each sample was globally fitted over triplicates and five rotor speeds. The exceptional stability of DNA allowed each sample to be sedimented repeatedly over the course of …

Testis-Specific Serine Kinase 3 Is Required For Sperm Morphogenesis And Male Fertility, Kaori Nozawa, Thomas X Garcia, Katarzyna Kent, Mei Leng, Antrix Jain, Anna Malovannaya, Fei Yuan, Zhifeng Yu, Masahito Ikawa, Martin M Matzuk

Faculty, Staff and Students Publications

BACKGROUND: The importance of phosphorylation in sperm during spermatogenesis has not been pursued extensively. Testis-specific serine kinase 3 (Tssk3) is a conserved gene, but TSSK3 kinase functions and phosphorylation substrates of TSSK3 are not known.

OBJECTIVE: The goals of our studies were to understand the mechanism of action of TSSK3.

MATERIALS AND METHODS: We analyzed the localization of TSSK3 in sperm, used CRISPR/Cas9 to generate Tssk3 knockout (KO) mice in which nearly all of the Tssk3 open reading frame was deleted (ensuring it is a null mutation), analyzed the fertility of Tssk3 KO mice by breeding mice for 4 months, …

Covet: A Covariation-Evolutionary Trace Method That Identifies Protein Structure-Function Modules, Daniel M Konecki, Spencer Hamrick, Chen Wang, Melina A Agosto, Theodore G Wensel, Olivier Lichtarge

Faculty, Staff and Students Publications

Measuring the relative effect that any two sequence positions have on each other may improve protein design or help better interpret coding variants. Current approaches use statistics and machine learning but rarely consider phylogenetic divergences which, as shown by Evolutionary Trace studies, provide insight into the functional impact of sequence perturbations. Here, we reframe covariation analyses in the Evolutionary Trace framework to measure the relative tolerance to perturbation of each residue pair during evolution. This approach (CovET) systematically accounts for phylogenetic divergences: at each divergence event, we penalize covariation patterns that belie evolutionary coupling. We find that while CovET approximates …

Targeting Aav Vectors To The Central Nervous System By Engineering Capsid-Receptor Interactions That Enable Crossing Of The Blood-Brain Barrier, Qin Huang, Albert T Chen, Ken Y Chan, Hikari Sorensen, Andrew J Barry, Bahar Azari, Qingxia Zheng, Thomas Beddow, Binhui Zhao, Isabelle G Tobey, Cynthia Moncada-Reid, Fatma-Elzahraa Eid, Christopher J Walkey, M Cecilia Ljungberg, William R Lagor, Jason D Heaney, Yujia A Chan, Benjamin E Deverman

Faculty, Staff and Students Publications

Viruses have evolved the ability to bind and enter cells through interactions with a wide variety of cell macromolecules. We engineered peptide-modified adeno-associated virus (AAV) capsids that transduce the brain through the introduction of de novo interactions with 2 proteins expressed on the mouse blood-brain barrier (BBB), LY6A or LY6C1. The in vivo tropisms of these capsids are predictable as they are dependent on the cell- and strain-specific expression of their target protein. This approach generated hundreds of capsids with dramatically enhanced central nervous system (CNS) tropisms within a single round of screening in vitro and secondary validation in vivo …

Outersphere Approach To Increasing The Persistance Of Oxygen-Sensitive Europium(Ii)-Containing Contrast Agents For Magnetic Resonance Imaging With Perfluorocarbon Nanoemulsions Toward Imaging Of Hypoxia, Jacob C Lutter, Andrea L Batchev, Caitlyn J Ortiz, Alexander G Sertage, Jonathan Romero, S A Amali S Subasinghe, Steen E Pedersen, Md Abul Hassan Samee, Robia G Pautler, Matthew J Allen

Faculty, Staff and Students Publications

Radiographic mapping of hypoxia is needed to study a wide range of diseases. Complexes of EuII are a promising class of molecules to fit this need, but they are generally limited by their rapid oxidation rates in vivo. Here, a perfluorocarbon-nanoemulsion perfused with N2, forms an interface with aqueous layers to hinder oxidation of a new perfluorocarbon-soluble complex of EuII. Conversion of the perfluorocarbon solution of EuII into nanoemulsions results in observable differences between reduced and oxidized forms by MRI both in vitro and in vivo. Oxidation in vivo occurrs over a period of ~30 min compared to <5 min for a comparable EuII-containing complex without nanoparticle interfaces. These results represent a critical step toward delivery of EuII-containing complexes in vivo for the study of hypoxia.