Medical Biochemistry Commons^™

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 …

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 …

Identification And Characterization Of Cannabichromene's Major Metabolite Following Incubation With Human Liver Microsomes, Alexandra M Ward, Touraj Shokati, Jost Klawitter, Jelena Klawitter, Vu Nguyen, Laura Kozell, Atheir I Abbas, David Jones, Uwe Christians

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Cannabichromene (CBC) is a minor cannabinoid within the array of over 120 cannabinoids identified in the Cannabis sativa plant. While CBC does not comprise a significant portion of whole plant material, it is available to the public in a purified and highly concentrated form. As minor cannabinoids become more popular due to their potential therapeutic properties, it becomes crucial to elucidate their metabolism in humans. Therefore, the goal of this was study to identify the major CBC phase I-oxidized metabolite generated in vitro following incubation with human liver microsomes. The novel metabolite structure was identified as 2′-hydroxycannabicitran using gas chromatography–mass …

Hammerhead-Type Fxr Agonists Induce An Enhancer Rna Fincor That Ameliorates Nonalcoholic Steatohepatitis In Mice, Jinjing Chen, Ruoyu Wang, Feng Xiong, Hao Sun, Byron Kemper, Wenbo Li, Jongsook Kemper

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The nuclear receptor, farnesoid X receptor (FXR/NR1H4), is increasingly recognized as a promising drug target for metabolic diseases, including nonalcoholic steatohepatitis (NASH). Protein-coding genes regulated by FXR are well known, but whether FXR also acts through regulation of long non-coding RNAs (lncRNAs), which vastly outnumber protein-coding genes, remains unknown. Utilizing RNA-seq and global run-on sequencing (GRO-seq) analyses in mouse liver, we found that FXR activation affects the expression of many RNA transcripts from chromatin regions bearing enhancer features. Among these we discovered a previously unannotated liver-enriched enhancer-derived lncRNA (eRNA), termed FXR-induced non-coding RNA (

Nanocavity-Mediated Purcell Enhancement Of Er In Tio2 Thin Films Grown Via Atomic Layer Deposition, Cheng Ji, Michael T Solomon, Gregory D Grant, Koichi Tanaka, Muchuan Hua, Jianguo Wen, Sagar Kumar Seth, Connor P Horn, Ignas Masiulionis, Manish Kumar Singh, Sean E Sullivan, F Joseph Heremans, David D Awschalom, Supratik Guha, Alan M Dibos

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The use of trivalent erbium (Er3+), typically embedded as an atomic defect in the solid-state, has widespread adoption as a dopant in telecommunication devices and shows promise as a spin-based quantum memory for quantum communication. In particular, its natural telecom C-band optical transition and spin-photon interface make it an ideal candidate for integration into existing optical fiber networks without the need for quantum frequency conversion. However, successful scaling requires a host material with few intrinsic nuclear spins, compatibility with semiconductor foundry processes, and straightforward integration with silicon photonics. Here, we present Er-doped titanium dioxide (TiO2) thin film growth on silicon …

Combined Ion Beam Irradiation Platform And 3d Fluorescence Microscope For Cellular Cancer Research, Andrew D Harken, Naresh T Deoli, Citlali Perez Campos, Brian Ponnaiya, Guy Garty, Grace S Lee, Malte J Casper, Shikhar Dhingra, Wenze Li, Gary W Johnson, Sally A Amundson, Peter W Grabham, Elizabeth M C Hillman, David J Brenner

Faculty, Staff and Student Publications

To improve particle radiotherapy, we need a better understanding of the biology of radiation effects, particularly in heavy ion radiation therapy, where global responses are observed despite energy deposition in only a subset of cells. Here, we integrated a high-speed swept confocally-aligned planar excitation (SCAPE) microscope into a focused ion beam irradiation platform to allow real-time 3D structural and functional imaging of living biological samples during and after irradiation. We demonstrate dynamic imaging of the acute effects of irradiation on 3D cultures of U87 human glioblastoma cells, revealing characteristic changes in cellular movement and intracellular calcium signaling following ionizing irradiation.

Biomechanical Analysis Of The Maxillary Sinus Floor Membrane During Internal Sinus Floor Elevation With Implants At Different Angles Of The Maxillary Sinus Angles, Yinxin Deng, Ruihong Ma, Yilin He, Shujia Yu, Shiyu Cao, Kang Gao, Yiping Dou, Pan Ma

Faculty, Staff and Student Publications

OBJECTIVE: This study analyzed and compared the biomechanical properties of maxillary sinus floor mucosa with implants at three different maxillary sinus angles during a modified internal sinus floor elevation procedure.

METHODS: 3D reconstruction of the implant, maxillary sinus bone, and membrane were performed. The maxillary sinus model was set at three different angles. Two internal maxillary sinus elevation models were established, and finite element analysis was used to simulate the modified maxillary sinus elevation process. The implant was elevated to 10 mm at three maxillary sinus angles when the maxillary sinus floor membrane was separated by 0 and 4 mm. …

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

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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.

Transcription Factor Bach1 In Cancer: Roles, Mechanisms, And Prospects For Targeted Therapy, Dian Hu, Zerui Zhang, Xiangyuan Luo, Siwen Li, Junqing Jiang, Jiaqian Zhang, Zhangfan Wu, Yijun Wang, Mengyu Sun, Xiaoping Chen, Bixiang Zhang, Xiao Xu, Shuai Wang, Shengjun Xu, Yufei Wang, Wenjie Huang, Limin Xia

Faculty, Staff and Student Publications

Transcription factor BTB domain and CNC homology 1 (BACH1) belongs to the Cap 'n' Collar and basic region Leucine Zipper (CNC-bZIP) family. BACH1 is widely expressed in mammalian tissues, where it regulates epigenetic modifications, heme homeostasis, and oxidative stress. Additionally, it is involved in immune system development. More importantly, BACH1 is highly expressed in and plays a key role in numerous malignant tumors, affecting cellular metabolism, tumor invasion and metastasis, proliferation, different cell death pathways, drug resistance, and the tumor microenvironment. However, few articles systematically summarized the roles of BACH1 in cancer. This review aims to highlight the research status …

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 …

Hnf4Α Isoforms Regulate The Circadian Balance Between Carbohydrate And Lipid Metabolism In The Liver, Jonathan R Deans, Poonamjot Deol, Nina Titova, Sarah H Radi, Linh M Vuong, Jane R Evans, Songqin Pan, Johannes Fahrmann, Jun Yang, Bruce D Hammock, Oliver Fiehn, Baharan Fekry, Kristin Eckel-Mahan, Frances M Sladek

Faculty, Staff and Student Publications

Hepatocyte Nuclear Factor 4α (HNF4α), a master regulator of hepatocyte differentiation, is regulated by two promoters (P1 and P2) which drive the expression of different isoforms. P1-HNF4α is the major isoform in the adult liver while P2-HNF4α is thought to be expressed only in fetal liver and liver cancer. Here, we show that P2-HNF4α is indeed expressed in the normal adult liver at Zeitgeber time (ZT)9 and ZT21. Using exon swap mice that express only P2-HNF4α we show that this isoform orchestrates a distinct transcriptome and metabolome via unique chromatin and protein-protein interactions, including with different clock proteins at different …

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

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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 …

Loss Of The Methylarginine Reader Function Of Snd1 Confers Resistance To Hepatocellular Carcinoma, Tanner Wright, Yalong Wang, Sabrina A Stratton, Manu Sebastian, Bin Liu, David G Johnson, Mark T Bedford

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Staphylococcal nuclease Tudor domain containing 1 (SND1) protein is an oncogene that 'reads' methylarginine marks through its Tudor domain. Specifically, it recognizes methylation marks deposited by protein arginine methyltransferase 5 (PRMT5), which is also known to promote tumorigenesis. Although SND1 can drive hepatocellular carcinoma (HCC), it is unclear whether the SND1 Tudor domain is needed to promote HCC. We sought to identify the biological role of the SND1 Tudor domain in normal and tumorigenic settings by developing two genetically engineered SND1 mouse models, an Snd1 knockout (Snd1 KO) and an Snd1 Tudor domain-mutated (Snd1 KI) mouse, whose mutant SND1 can …

Conformational Ensemble-Dependent Lipid Recognition And Segregation By Prenylated Intrinsically Disordered Regions In Small Gtpases, Mussie K Araya, Alemayehu A Gorfe

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We studied diverse prenylated intrinsically disordered regions (PIDRs) of Ras and Rho family small GTPases using long timescale atomistic molecular dynamics simulations in an asymmetric model membrane of phosphatidylcholine (PC) and phosphatidylserine (PS) lipids. Here we show that conformational plasticity is a key determinant of lipid sorting by polybasic PIDRs and provide evidence for lipid sorting based on both headgroup and acyl chain structures. We further show that conformational ensemble-based lipid recognition is generalizable to all polybasic PIDRs, and that the sequence outside the polybasic domain (PBD) modulates the conformational plasticity, bilayer adsorption, and interactions of PIDRs with membrane lipids. …

The Effect Of Heat-Moisture Treatment Changed The Binding Of Starch, Protein And Lipid In Rice Flour To Affect Its Hierarchical Structure And Physicochemical Properties, Seung Hee Yoo, Mi Jin Jue, Yu-Hee Kim, Sooyoung Cho, Won-Joong Kim, Kye-Min Kim, Jong In Han, Heeseung Lee

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Dexmedetomidine prevents postoperative cognitive dysfunction by inhibiting high-mobility group box 1 (HMGB1), which acts as an inflammatory marker. This study investigated the HMGB1 levels and the cognitive function using a Mini-Cog© score in elderly patients undergoing orthopedic surgery with dexmedetomidine infusion. In total, 128 patients aged ≥ 65 years were analyzed. The patients received saline in the control group and dexmedetomidine in the dexmedetomidine group until the end of surgery. Blood sampling and the Mini-Cog© test were performed before the surgery and on postoperative days 1 and 3. The primary outcomes were the effect of dexmedetomidine on the HMGB1 levels …

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: …

Direct Modulators Of K-Ras–Membrane Interactions, Johannes Morstein, Rebika Shrestha, Que N Van, César A López, Neha Arora, Marco Tonelli, Hong Liang, De Chen, Yong Zhou, John F Hancock, Andrew G Stephen, Thomas J Turbyville, Kevan M Shokat

Faculty, Staff and Student Publications

Protein-membrane interactions (PMIs) are ubiquitous in cellular signaling. Initial steps of signal transduction cascades often rely on transient and dynamic interactions with the inner plasma membrane leaflet to populate and regulate signaling hotspots. Methods to target and modulate these interactions could yield attractive tool compounds and drug candidates. Here, we demonstrate that the conjugation of a medium-chain lipid tail to the covalent K-Ras(G12C) binder MRTX849 at a solvent-exposed site enables such direct modulation of PMIs. The conjugated lipid tail interacts with the tethered membrane and changes the relative membrane orientation and conformation of K-Ras(G12C), as shown by molecular dynamics (MD) …

The Classification Of Obesity Based On Metabolic Status Redefines The Readmission Of Non-Hodgkin’S Lymphoma—An Observational Study, Eunju Kim, Kazuaki Mawatari, Seung-Hee Yoo, Zheng Chen

Faculty, Staff and Student Publications

Obesity is a known risk factor for metabolic diseases and is often associated with chronic inflammation in adipose tissue. We previously identified the polyethoxylated flavonoid Nobiletin (NOB) as a circadian clock modulator that directly binds to and activates the ROR receptors in the core oscillator, markedly improving metabolic fitness in obese mice. Here, we show that NOB enhanced the oscillation of core clock genes in differentiated 3T3-L1 adipocytes, including ROR target genes such as Bmal1, Cry1, Dec1, and Dec2. NOB inhibited lipid accumulation in 3T3-L1 and SVF cells, concomitant with the dysregulated circadian expression of adipogenic …

Effects Of Surface Treatment Method Forming New Nano/Micro Hierarchical Structures On Attachment And Proliferation Of Osteoblast-Like Cells, Jae-Seung Im, Hyunsuk Choi, Hyun-Wook An, Tae-Yub Kwon, Min-Ho Hong

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Titanium (Ti) and Ti-based alloys are commonly used in dental implants, and surface modifications of dental implants are important for achieving osseointegration (i.e., direct connection between the implant surface and bone). This study investigated the effect of an eco-friendly etching solution-a hydrogen peroxide-sodium bicarbonate mixture-on the surface properties and contact angles of osteoblast adhesion and proliferation on Ti surfaces. Disk-shaped Ti specimens were prepared using different surface treatments (machining, sandblasting, and sandblasting/acid-etching), and they were immersed in the etching solution and ultrasonically cleaned. Surface characterization was performed using scanning electron microscopy, digital microscopy, contact angle analysis, and X-ray photoelectron spectroscopy. …

Src Stimulates Abl-Dependent Phosphorylation Of The Guanine Exchange Factor Net1a To Promote Its Cytosolic Localization And Cell Motility, Ashabari Sprenger, Heather S Carr, Arzu Ulu, Jeffrey A Frost

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The neuroepithelial cell transforming gene 1 (Net1) is a guanine nucleotide exchange factor for the small GTPase RhoA that promotes cancer cell motility and metastasis. Two isoforms of Net1 exist, Net1 and Net1A, both of which are sequestered in the nucleus in quiescent cells to prevent aberrant RhoA activation. Many cell motility stimuli drive cytosolic relocalization of Net1A, but mechanisms controlling this event are not fully understood. Here, we demonstrate that epithelial growth factor stimulates protein kinase Src- and Abl1-dependent phosphorylation of Net1A to promote its cytosolic localization. We show that Abl1 efficiently phosphorylates Net1A on Y373, and that phenylalanine …

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

Faculty, Staff and Student Publications

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

Ca2+ Efflux Facilitated By Co-Transport Of Inorganic Phosphate Anion In The H+/Ca2+ Antiporter Yfke, Wei Niu, Wenchang Zhou, Shuo Lu, Trung Vu, Vasanthi Jayaraman, José D Faraldo-Gómez, Lei Zheng

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Ca2+ is an important signaling messenger. In microorganisms, fungi, and plants, H+/Ca2+ antiporters (CAX) are known to play key roles in the homeostasis of intracellular Ca2+ by catalyzing its efflux across the cell membrane. Here, we reveal that the bacterial CAX homolog YfkE transports Ca2+ in two distinct modes: a low-flux H+/Ca2+ exchange mode and a high-flux mode in which Ca2+ and phosphate ions are co-transported (1:1) in exchange for H+. Coupling with phosphate greatly accelerates the Ca2+ efflux activity of YfkE. Our studies reveal that Ca2+ and phosphate bind to adjacent sites in a central translocation pathway and lead …

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

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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 …

Bone Marrow Endosteal Stem Cells Dictate Active Osteogenesis And Aggressive Tumorigenesis, Yuki Matsushita, Jialin Liu, Angel Ka Yan Chu, Chiaki Tsutsumi-Arai, Mizuki Nagata, Yuki Arai, Wanida Ono, Kouhei Yamamoto, Thomas L Saunders, Joshua D Welch, Noriaki Ono

Faculty, Staff and Student Publications

The bone marrow contains various populations of skeletal stem cells (SSCs) in the stromal compartment, which are important regulators of bone formation. It is well-described that leptin receptor (LepR)+ perivascular stromal cells provide a major source of bone-forming osteoblasts in adult and aged bone marrow. However, the identity of SSCs in young bone marrow and how they coordinate active bone formation remains unclear. Here we show that bone marrow endosteal SSCs are defined by fibroblast growth factor receptor 3 (Fgfr3) and osteoblast-chondrocyte transitional (OCT) identities with some characteristics of bone osteoblasts and chondrocytes. These Fgfr3-creER-marked endosteal stromal cells contribute to …

Successful Heart-Liver Transplant Using Dual-Organ Normothermic Perfusion In A Patient With Fontan Failure, Anton Kozyryev, Daniel Lemen, Jessica Dunn, Steven E Rokita

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Iodotyrosine deiodinase (IYD) is unusual in its reliance on flavin to promote reductive dehalogenation of halotyrosines under aerobic conditions. Applications of this activity can be envisioned for bioremediation, but expansion of its specificity requires an understanding of the mechanistic steps that limit the rate of turnover. Key processes capable of controlling steady-state turnover have now been evaluated and described in this study. While proton transfer is necessary for converting the electron-rich substrate into an electrophilic intermediate suitable for reduction, kinetic solvent deuterium isotope effects suggest that this process does not contribute to the overall efficiency of catalysis under neutral conditions. …

Mechanosensitive Membrane Proteins: Usual And Unusual Suspects In Mediating Mechanotransduction, Miriam B Goodman, Elizabeth S Haswell, Valeria Vásquez

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This Viewpoint, which accompanies a Special Issue focusing on membrane mechanosensors, discusses unifying and unique features of both established and emerging mechanosensitive (MS) membrane proteins, their distribution across protein families and phyla, and current and future challenges in the study of these important proteins and their partners. MS membrane proteins are essential for tissue development, cellular motion, osmotic homeostasis, and sensing external and self-generated mechanical cues like those responsible for touch and proprioception. Though researchers' attention and this Viewpoint focus on a few famous ion channels that are considered the usual suspects as MS mechanosensors, we also discuss some of …

A Complete Methyl-Lysine Binding Aromatic Cage Constructed By Two Domains Of Phf2, John R Horton, Jujun Zhou, Qin Chen, Xing Zhang, Mark T Bedford, Xiaodong Cheng

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The N-terminal half of PHF2 harbors both a plant homeodomain (PHD) and a Jumonji domain. The PHD recognizes both histone H3 trimethylated at lysine 4 and methylated nonhistone proteins including vaccinia-related kinase 1 (VRK1). The Jumonji domain erases the repressive dimethylation mark from histone H3 lysine 9 (H3K9me2) at select promoters. The N-terminal amino acid sequences of H3 (AR2TK4) and VRK1 (PR2VK4) bear an arginine at position 2 and lysine at position 4. Here, we show that the PHF2 N-terminal half binds to H3 and VRK1 peptides containing K4me3, with dissociation constants (KD values) of 160 nM and 42 nM, …

Sgc-Camkk2-1: A Chemical Probe For Camkk2, Carrow Wells, Yi Liang, Thomas L Pulliam, Chenchu Lin, Dominik Awad, Benjamin Eduful, Sean O'Byrne, Mohammad Anwar Hossain, Carolina Moura Costa Catta-Preta, Priscila Zonzini Ramos, Opher Gileadi, Carina Gileadi, Rafael M Couñago, Brittany Stork, Christopher G Langendorf, Kevin Nay, Jonathan S Oakhill, Debarati Mukherjee, Luigi Racioppi, Anthony R Means, Brian York, Donald P Mcdonnell, John W Scott, Daniel E Frigo, David H Drewry

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The serine/threonine protein kinase calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) plays critical roles in a range of biological processes. Despite its importance, only a handful of inhibitors of CAMKK2 have been disclosed. Having a selective small molecule tool to interrogate this kinase will help demonstrate that CAMKK2 inhibition can be therapeutically beneficial. Herein, we disclose SGC-CAMKK2-1, a selective chemical probe that targets CAMKK2.

Effects Of Atrazine Exposure On Human Bone Marrow-Derived Mesenchymal Stromal Cells Assessed By Combinatorial Assay Matrix, Crystal C Uwazie, Bonnie M Pirlot, Tyler U Faircloth, Mihir Patel, Rhett N Parr, Halie M Zastre, Peiman Hematti, Guido Moll, Devi Rajan, Raghavan Chinnadurai

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INTRODUCTION: Mesenchymal Stromal/Stem cells (MSCs) are an essential component of the regenerative and immunoregulatory stem cell compartment of the human body and thus of major importance in human physiology. The MSCs elicit their beneficial properties through a multitude of complementary mechanisms, which makes it challenging to assess their phenotype and function in environmental toxicity screening. We here employed the novel combinatorial assays matrix approach/technology to profile the MSC response to the herbicide Atrazine, which is a common environmental xenobiotic, that is in widespread agricultural use in the US and other countries, but banned in the EU. Our here presented approach …