Medicine and Health Sciences Commons^™

Convergent Reduction Of Olfactory Genes And Olfactory Bulb Size In Mammalian Species At Altitude, Allie M Graham, Elysia Saputra, Bogdan Kirilenko, Jason S Presnell, Arianna Harrington, Chad Huff, Michael Hiller, Nathan Clark

Faculty, Staff and Student Publications

The invasion of specialized ecological niches can cause drastic changes to selection regimes, resulting in genomic and phenotypic transformation.

Retinal Ganglion Cell Migration And Viability Requires The Kinase Lkb1, Robert D Mackin, Ritika V Bhalla, Viktor Akhanov, Qudrat T Abdulwahab, Courtney A Burger, Melanie A Samuel

Faculty, Staff and Students Publications

The arrangement of neurons into ordered layers underlies circuit function in many nervous system regions. This is particularly true in the mammalian retina. Here, fate-committed retinal ganglion cells (RGCs) migrate from the apical to the inner retina, where they form connections that enable vision. The mechanisms that permit ganglion cell migration and whether distinct ganglion cell types use different migration modes are unknown. We show that the serine/threonine kinase LKB1 regulates ganglion cell migration and nuclear positioning. In the absence of LKB1, many ganglion cells remain in the apical retina. Misplaced cells show modified morphologies and display altered cytoskeletal proteins. …

Disruption Of A Side Portal Pathway Permits Closed-State Inactivation By Bk Β Subunit N Termini, Yu Zhou, Xiao-Ming Xia, Christopher J Lingle

2020-Current year OA Pubs

Cytosolic N termini of several BK channel β regulatory subunits mediate rapid inactivation. However, in contrast to Kv channels, inactivation does not occur via a simple, open-channel block mechanism, but involves two steps, an association step in which ion permeation is maintained (O*), then followed by inactivation (I). To produce inactivation, BK β subunit N termini enter the central cavity through a lateral entry pathway ("side portal") separating the transmembrane pore-gate domain and cytosolic gating ring. Comparison of BK conformations reveals an aqueous pathway into the central cavity in the open structure, while in the closed structure, three sequential basic …

Coresh: A Gene Signature-Based Search Engine For Public Gene Expression Datasets, Vladimir Sukhov, Aigul Nugmanova, Yury Vorontsov, Parul Mehrotra, Maksim Kleverov, Kodi Ravichandran, Maxim Artyomov, Alexey Sergushichev

2020-Current year OA Pubs

Public data repositories like Gene Expression Omnibus (GEO) contain an extensive amount of data from hundreds of thousands of experiments, making them a valuable resource for researchers. A common scenario for utilizing this resource is to show transcriptional similarity of one's own data to a public dataset as evidence of potentially similar biology. However, when searching for such datasets, researchers are usually limited to keyword-based search, which requires having a specific hypothesis and relies on the presence of high-quality metadata in public datasets. Here, we introduce CORESH, a web server designed to systematically find GEO datasets that match a user-provided …

Loss Of Intracellular Fgf14 (Ifgf14) Increases Excitability Of Mature Hippocampal Pyramidal Neurons, Joseph L Ransdell, Yarimar Carrasquillo, Marie K Bosch, Rebecca L Mellor, David M Ornitz, Jeanne M Nerbonne

2020-Current year OA Pubs

Mutations in FGF14, which encodes intracellular fibroblast growth factor 14 (iFGF14), have been linked to spinocerebellar ataxia type 27 (SCA27), a multisystem disorder associated with deficits in motor coordination and cognitive function. Mice lacking iFGF14 (Fgf14-/-) display similar phenotypes, and we have previously shown that the deficits in motor coordination reflect reduced excitability of cerebellar Purkinje neurons, owing to a hyperpolarizing shift in the voltage-dependence of voltage-gated Na+ (Nav) current steady-state inactivation. Here, we present the results of experiments designed to test the hypothesis that loss of iFGF14 also attenuates the intrinsic excitability of mature hippocampal pyramidal neurons. Current-clamp recordings …

Highly Sensitive In Vivo Detection Of Dynamic Changes In Enkephalins Following Acute Stress In Mice, Marwa O Mikati, Petra Erdmann-Gilmore, Rose Connors, Sineadh M Conway, Jim Malone, Justin Woods, Robert W Sprung, Reid R Townsend, Ream Al-Hasani

2020-Current year OA Pubs

Enkephalins are opioid peptides that modulate analgesia, reward, and stress. In vivo detection of enkephalins remains difficult due to transient and low endogenous concentrations and inherent sequence similarity. To begin to address this, we previously developed a system combining in vivo optogenetics with microdialysis and a highly sensitive mass spectrometry-based assay to measure opioid peptide release in freely moving rodents (Al-Hasani et al., 2018, eLife). Here, we show improved detection resolution and stabilization of enkephalin detection, which allowed us to investigate enkephalin release during acute stress. We present an analytical method for real-time, simultaneous detection of Met- and Leu-enkephalin (Met-Enk …

Mesenchymal Stem Cell-Derived Extracellular Vesicles: Seeking Into Cell-Free Therapies For Bone-Affected Lysosomal Storage Disorders, Andrés Felipe Leal, Harry Pachajoa, Shunji Tomatsu

Department of Pediatrics Faculty Papers

Lysosomal storage disorders (LSDs) constitute a group of monogenic systemic diseases resulting from deficiencies in specific lysosomal enzymes that cause the intralysosomal accumulation of non- or partially degraded substrates, leading to lysosomal dysfunction. In some cases of LSDs, the bone is more severely affected, thus producing skeletal manifestations in patients. Current therapies, such as enzyme replacement therapy (ERT) and gene therapy (GT), show limited efficacy in correcting skeletal abnormalities. Increasing evidence suggests that microenvironmental disturbances also contribute significantly to disease pathogenesis. Therefore, therapeutic strategies targeting lysosomal dysfunction and microenvironmental dysregulation are needed. Mesenchymal stem-cell-derived extracellular vesicles (MSC-EVs) are emerging as …

Transcriptomic And Histological Characteristics Of Innate Immune Activation In Brain Parenchyma In A Rat Model Of Neonatal Intraventricular Hemorrhage, Miriam Zamorano, Sanjna Udtha, Aidan M Collier, Erica Underwood, Razan El Sayed, Ankit Agarwal, Devin S Hatchell, Chunfeng Tan, Paul J Nietert, Scott D Olson, Brandon A Miller

Faculty, Staff and Student Publications

Background: Intraventricular hemorrhage (IVH) remains a major complication in preterm infants with lifelong sequelae. There is no effective treatment for IVH other than supportive care and surgery for post-hemorrhagic hydrocephalus. We previously reported that the innate neuroimmune response in an animal model of IVH was dependent on developmental stage, only occurring in older animals.

Methods: This study utilized a lysed-blood injection model of IVH in rats. This model specifically captures the effects of blood products released by IVH on brain parenchyma. We performed RNAseq and differential gene expression analysis on CD11b/c-positive cells in the brain (microglia/macrophages) to define gene expression …

Parkinson Disease Signaling Pathways, Molecular Mechanisms, And Potential Therapeutic Strategies: A Comprehensive Review, Muhammad S Khan, Somayyeh Nasiripour, Jean C Bopassa

Faculty, Staff and Student Publications

Parkinson's disease (PD) is considered the second most common neurodegenerative disease worldwide; treating this disease remains quite challenging. Environmental and genetic factors may play a role in the pathophysiology of PD. α-synuclein aggregation, oxidative stress, ferroptosis, mitochondrial failure, neuroinflammation, and gut dysbiosis are among the known risk factors of PD. The pathophysiology of Parkinson's disease is complicated by the interconnections between these molecular pathways, which also present significant obstacles to treatment development. However, due to its complex mechanism and long latency, PD is difficult to diagnose and detect, which presents a barrier to treatment. In addition, the need to develop …

Direct Inhibition Of Ras Reveals The Features Of Oncogenic Signaling Driven By Ras G12 And Q61 Mutations, Michelangelo Marasco, Dinesh Kumar, Santiago Garcia Borrego, Tessa Seale, Giulia Maddalena, Riccardo Mezzadra, Kylie Belanger, Soren Cole, Brayan Perez, Wei Luan, Radha Mukherjee, Ilinca Aricescu, Vladimir Markov, Yuxin Zhu, Sabrina Arena, Alberto Bardelli, Elisa De Stanchina, Scott W Lowe, Richard A Burkhart, Jacquelyn W Zimmerman, Rona Yaeger, Scott E Kopetz, Neal Rosen, Sandra Misale

Faculty, Staff and Student Publications

RAS genes are frequently mutated in cancer, often at codons 12 and 61. With the recent introduction of RAS inhibitors, we can now directly investigate the effects of specific RAS mutations in cancer cells. In this study, we demonstrate that in tumors with RASG12X mutations, mutant RAS can be activated by receptor tyrosine kinases (RTK), and PI3K activation is dependent on mutant RAS. Conversely, RASQ61X mutations activate the MAPK cascade independently of RTKs, and inhibition of RASQ61X impairs MAPK pathway activation but leaves the PI3K pathway unaffected. Our characterization of these distinct features of G12X and Q61X mutations suggests that …

Recurrent De Novo Variants In The Spliceosomal Factor Crnkl1 Are Associated With Severe Microcephaly And Pontocerebellar Hypoplasia With Seizures, Sankalita Ray Das, Rosie Sullivan, Mischa S G Ruegg, Julia Horsfield, Jordan Doran, Gemma Poke, Nathalie De Vries, Sarah Duerinckx, Damien Lederer, Muzhirah Haniffa, Wee-Teik Keng, Gaik-Siew Ch'ng, David A Parry, Andrew P Jackson, Masamune Sakamoto, Naomichi Matsumoto, Noriko Miyake, Shin Nabatame, Hidetoshi Taniguchi, Emma Wakeling, Katrin Õunap, Pilvi Ilves, Ghayda Mirzaa, Andrew Timms, Emily Pao, Kimberly A Aldinger, William Dobyns, Axel Bohring, Beate Behre, Daniel G Calame, James R Lupski, Juan M Pascual, Marc Abramowicz, Gregory Gimenez, Louise S Bicknell

Faculty, Staff and Students Publications

Splicing is a complex process that is required to create the transcriptomic diversity needed for specialized functions in higher eukaryotes. The spliceosome contains more than 100 proteins and RNA molecules, which coordinate this dynamic process. Despite the ubiquity of splicing, pathogenic variants in spliceosomal components often cause a tissue-specific phenotype, hinting at further complexities that are not yet fully understood. We have identified a cohort of ten families with de novo missense variants in a spliceosomal component, CRNKL1, where nine individuals harbor one of two missense variants that both affect the same amino acid, Arg267. All affected individuals share a …

Hallmarks Of Stem Cell Aging, Thomas A Rando, Anne Brunet, Margaret A Goodell

Faculty, Staff and Students Publications

As organisms age, somatic stem cells progressively lose their ability to sustain tissue homeostasis and support regeneration. Although stem cells are relatively shielded from some cellular aging mechanisms compared with their differentiated progeny, they remain vulnerable to both intrinsic and extrinsic stressors. In this review, we delineate five cardinal features that characterize aged stem cells and examine how these alterations underlie functional decline across well-studied stem cell compartments. These hallmarks not only provide insight into the aging process but also serve as promising targets for therapeutic strategies aimed at rejuvenating stem cell function and extending tissue health span.

The Trapping Of Live Neutrophils By Macrophages During Infection, Kelley N Cooper, Marina Terekhova, Barbara Potempa, Ana D'Aubeterre, Jerome Timbol, Si An Chen, Antoine Dufour, Shunying Jin, Maxim N Artyomov, Jan Potempa, Juhi Bagaitkar

2020-Current year OA Pubs

Neutrophils are highly abundant in the oral mucosal tissues, and their balanced activation and clearance are essential for immune homeostasis. Here, we demonstrate that neutrophils infected with the bacterial pathogen Porphyromonas gingivalis (Pg) are captured alive by macrophages in a manner that bypasses all known receptor-ligand interactions involved in the phagocytosis of either live or dead cells. Mechanistically, upon interaction with Pg, or its protease RgpB (gingipains), live neutrophils undergo rapid remodeling of their proteomes, generating neoepitopes. N-terminomics-based proteomic profiling identified multiple RgpB cleavage sites on several azurophilic granule proteins that are translocated to the surface of live neutrophils via …

Amino Acid Transporter Lat1 (Slc7a5) Promotes Metabolic Rewiring In Tnbc Progression Through The L-Trp/Qprt/Nad+ Pathway, Margot Y. Fedoroff, Lei Zhao, Shaomin Wang, Alok Bhushan, Haifeng Yang, Karen M. Bussard, Stephen C. Peiper, Jun He

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Cancer cells uptake excessive nutrients by expressing higher levels of glucose and/or amino acid transporters to meet their increased energy demands. L-type amino acid transporter 1 (LAT1), is regarded as a cancer-specific transporter for the uptake of large neutral amino acids such as L-tryptophan. However, the mechanism by which LAT1 rewires cellular metabolism to promote cancer progression and chemoresistance have not yet been investigated.

METHODS: The protein levels of LAT1, p-PKM2, and p-LDHA were determined in breast cancer tissue arrays by immunohistochemistry staining followed by survival analysis. The orthotopic breast cancer models in mice, syngeneic breast cancer models, and …

Quantum Magnetization Exchange Through Transient Hydrogen Bond Matrix Defines Magnetic Resonance Signal Relaxation And Anisotropy In Central Nervous System, Dmitriy A Yablonskiy, Alexander L Sukstanskii

2020-Current year OA Pubs

The integrity of cellular membranes (lipid bilayers) and myelin sheaths covering axons is a crucial feature controlling normal brain structural and functional networks. Yet, in vivo evaluation of this integrity at the nanoscale level of the cellular membranes organization is challenging. Herein we explore the dual property of biological water in Central Nervous System (CNS), as one of the major stabilizing factors of cellular membranes, and the major source of MRI signal. We introduce the Basic Transient Hydrogen Bond (THB) model of the MR signal relaxation due to the quantum spin/magnetization exchanges within the THB Matrix encompassing water molecules and …

Irradiation Of Prostate Cancer Alters Circulating Small Extracellular Vesicle Functions, Aejaz Sayeed, Vaughn Garcia, Cecilia E. Verrillo, Rachel M. Derita, Md Niamat Hossain, Shiv R. Krishn, Samuel Sey, Christopher D. Shields, Adrian D. Altieri, Qin Liu, Khalid Sossey-Alaoui, William K. Kelly, Lucia R. Languino

Department of Pharmacology, Physiology, and Cancer Biology Faculty Papers

It is known that β1 integrins and a downstream signaling molecule c-Src are upregulated in prostate cancer (PrCa) tissues, are co-expressed in circulating small extracellular vesicles (sEVs) and contribute to cancer progression. Here, we demonstrate that sEVs from PrCa patients show robust expression of both β1 integrins and c-Src. The impact of irradiation, a widely used therapy for the treatment of PrCa, on circulating sEVs is however not fully understood. We show that sEVs isolated from the plasma of transgenic adenocarcinoma of mouse prostate (TRAMP) mice, stimulate migration and anchorage-independent growth of recipient cancer cells, but sEVs are not active …

A Hedgehog-Foxf Axis Coordinates Dental Follicle-Derived Alveolar Bone Formation, Mizuki Nagata, Gaurav T Gadhvi, Taishi Komori, Yuki Arai, Chiaki Tsutsumi-Arai, Angel Ka Yan Chu, Seth N Nye, Yuntao Yang, Shion Orikasa, Akira Takahashi, Peter Carlsson, W Jim Zheng, Joshua D Welch, Noriaki Ono, Wanida Ono

Faculty, Staff and Student Publications

The alveolar bone is a specialized mineralized structure supporting the lifelong functionality of the tooth in mastication. The alveolar bone develops from the dental follicle (DF) during tooth root formation due to deliberate epithelial-mesenchymal interactions. However, how DF progenitor cell fates are regulated toward alveolar bone osteoblasts remains unknown. We find that Hedgehog signaling activities are transiently activated during the onset of tooth root formation and alveolar bone formation. Parathyroid hormone-related protein (PTHrP)-expressing DF cells are highly responsive to Hedgehog signaling, yet constitutive Hedgehog activation using Pthrp-creER and Ptch1-floxed alleles potently suppresses alveolar osteoblast and ligament differentiation of PTHrP+ DF …

Oxytocin Reduces Asymmetries In Dominance Relationships Between Pairs Of Captive Female Lions, Jessica C Burkhart, Abby Guthmann, Evianne M Dubois, Sarah R Heilbronner, Craig Packer

Faculty, Staff and Students Publications

Free-ranging female African lions maintain symmetrical social relationships by respecting each other's "ownership" of valuable food items rather than by supplanting subordinates according to well-defined dominance hierarchies. However, captivity often skews relationships in captive carnivores, hence we investigated whether captive female lions demonstrate obvious dominance relationships. Oxytocin has been shown to elicit context-specific impacts that equalize dominant subordinate relationships, thus we hypothesized that oxytocin would reduce any asymmetries found between dominants and subordinates in captive lions. We designed two experimental protocols for investigating pairwise relationships. We first identified dominant individuals by performing neutral trials that allowed each female equal opportunity …

Immature Acta2r179c/+ Smooth Muscle Cells Cause Moyamoya-Like Cerebrovascular Lesions In Mice Prevented By Boosting Oxphos, Anita Kaw, Suravi Majumder, Jose E Esparza Pinelo, Ting Wu, Zbigniew Starosolski, Zhen Zhou, Albert J Pedroza, Xueyan Duan, Kaveeta Kaw, Angie D Gonzalez, Ripon Sarkar, Michael P Fischbein, Philip L Lorenzi, Lin Tan, Sara A Martinez, Iqbal Mahmud, Laxman Devkota, L Maximilian Buja, Heinrich Taegtmeyer, Ketan B Ghaghada, Sean P Marrelli, Callie S Kwartler, Dianna M Milewicz

Faculty, Staff and Student Publications

ACTA2 pathogenic variants altering arginine 179 cause childhood-onset strokes due to moyamoya disease (MMD)-like occlusions of the distal internal carotid arteries, but the mechanisms of pathogenesis are unknown and no preventive treatments exist. Here we show that Acta2R179C/+ smooth muscle cells (SMCs) fail to fully differentiate and maintain stem cell-like features, including increased migration and glycolytic flux compared to wildtype (WT) SMCs. Increasing mitochondrial respiration with nicotinamide riboside (NR) drives differentiation and decreases migration of Acta2R179C/+ SMCs. Carotid artery injury of Acta2SMC-R179C/+ mice leads to premature death, intraluminal SMC accumulation leading to MMD-like occlusive lesions, neurologic symptoms, …

Pilot Survey Of Attitudes Toward Xenotransplantation Among Nursing Students In London, Uk., Daniel Rodger, Luz A. Padilla, Daniel J. Hurst, David K C Cooper, Gilberto Buzzi, Antonio Ríos

Rowan-Virtua School of Osteopathic Medicine Departmental Research

BACKGROUND: Solid organ xenotransplantation has been approved for clinical trials in the United States. Because of the role of nurses in patient decision-making, it is important to understand the attitudes of the future nursing workforce toward xenotransplantation. This pilot study aimed to investigate the attitudes of adult nursing students toward xenotransplantation.

METHODS: A cross-sectional survey design was used. The online pilot survey was completed by 33 undergraduate adult nursing students at one university in London, England. A minority of the hospitals that students may have had a clinical placement in had a transplant unit. The protocol for this study was …

C-Terminal Frameshift Variants In Gpkow Are Associated With A Multisystemic X-Linked Disorder, Jung-Wan Mok, Laura Mackay, Maria Blazo, Elizabeth Mizerik, Jozef Gecz, Renee Carroll, Mathilde Nizon, Sophie Rondeau, Madeleine Joubert, Silvestre Cuinat, Wallid Deb, Fernanda Valle Sirias, Monika Weisz-Hubshman, Shamika Ketkar, Urszula Polak, Alyssa A Tran, Debra Kearney, Neil A Hanchard, Oguz Kanca, Michael F Wangler, Hugo J Bellen, Brendan H Lee, Shinya Yamamoto, Keren Machol

Duncan NRI Faculty and Staff Publications

Purpose: GPKOW, a gene on the X-chromosome, encodes a nuclear RNA-binding protein important in messenger RNA (mRNA) processing as a spliceosome subunit. This work aims to establish GPKOW as a disease-associated gene.

Methods: We describe 3 males from 2 unrelated families with hemizygous frameshift variants affecting the last exon of GPKOW p.(Arg441SerfsTer30) and p.(Ser444GlufsTer28). The effect of p.(Ser444GlufsTer28) on gene expression was evaluated in patient's fibroblasts. In vivo studies in Drosophila melanogaster targeting the sole GPKOW fly ortholog, CG10324 (Gpkow) were performed.

Results: Clinical presentations included intrauterine growth restriction, microcephaly/microencephaly, and eye, brain, skin, and skeletal abnormalities. Heterozygote females presented …

Reduction Of Neuronal Activity Mediated By Blood-Vessel Regression In The Adult Brain, Xiaofei Gao, Xing-Jun Chen, Meng Ye, Jun-Liszt Li, Nannan Lu, Di Yao, Bo Ci, Fei Chen, Lijun Zheng, Yating Yi, Shiwen Zhang, Zhanying Bi, Xinwei Gao, Yuanlei Yue, Tingbo Li, Jiafu Lin, Ying-Chao Shi, Kaibin Shi, Nicholas E Propson, Yubin Huang, Katherine Poinsatte, Zhaohuan Zhang, Dale B Bosco, Shi-Bing Yang, Ralf H Adams, Volkhard Lindner, Fen Huang, Long-Jun Wu, Hui Zheng, Simon Hippenmeyer, Ann M Stowe, Bo Peng, Marta Margeta, Qingchun Guo, Xiaoqun Wang, Qiang Liu, Jakob Körbelin, Martin Trepel, Hui Lu, Guoen Cai, Bo O Zhou, Bo Shen, Ying-Mei Lu, Wenzhi Sun, Jie-Min Jia, Feng Han, Hu Zhao, Robert M Bachoo, Woo-Ping Ge

Center on Aging Staff Publications

The brain vasculature supplies neurons with glucose and oxygen, but little is known about how vascular plasticity contributes to brain function. Using longitudinal in vivo imaging, we report that a substantial proportion of blood vessels in the adult mouse brain sporadically occlude and regress. Their regression proceeds through sequential stages of blood-flow occlusion, endothelial cell collapse, relocation or loss of pericytes, and retraction of glial endfeet. Regressing vessels are found to be widespread in mouse, monkey and human brains. We further reveal that blood vessel regression cause a reduction of neuronal activity due to a dysfunction in mitochondrial metabolism and …

The Loss Of Opa1 Accelerates Intervertebral Disc Degeneration And Osteoarthritis In Aged Mice, Vedavathi Madhu, Miriam Hernandaz-Meadows, Ashley Coleman, Kimheak Sao, Kameron Inguito, Owen Haslam, Paige Boneski, Hiromi Sesaki, Ruteja Barve, John Collins, Makarand Risbud

Department of Orthopaedic Surgery Faculty Papers

Recent studies have highlighted the importance of mitochondria in NP cells and articular chondrocyte health. Since the understanding of mechanisms governing mitochondrial dynamics in these tissues is lacking, we investigated the role of OPA1, a mitochondrial fusion protein, in their homeostasis. OPA1 knockdown in NP cells altered mitochondrial size and cristae shape and increased the oxygen consumption rate. OPA1 governed the morphology of multiple organelles, including peroxisomes, early endosomes and cis-Golgi and loss resulted in the dysregulation of autophagy. Metabolic profiling and

Renal G Protein-Coupled Estrogen Receptor 1 Regulates The Epithelial Sodium Channel Promoting Natriuresis To A Greater Extent In Females, Victoria L Nasci, Jean C Bopassa, Elena Mironova, Megan Rhoads, Ravneet Singh, Dennis P Buehler, David M Pollock, Oleh M Pochynyuk, James D Stockand, Eman Y Gohar

Faculty, Staff and Student Publications

Hypertension prevalence is lower in women than men. Enhanced renal sodium (Na+) handling in females has been implicated in sex-differences in hypertension. Epithelial Na+ channel (ENaC) is a key contributor to Na+ homeostasis and is regulated by estrogen. Recent evidence suggests G protein-coupled estrogen receptor 1 (GPER1) evokes a female-specific natriuresis that involves endothelin-1 (ET-1). ET-1 has been shown to downregulate ENaC activity, but whether GPER1 regulates ENaC to modulate natriuresis is unknown. We tested the hypothesis that renal GPER1 functionally interacts with ENaC to promote natriuresis in a sex-specific manner. RNAscope confirmed co-expression of GPER1 and ENaC in rat …

Muscle Rev-Erb Controls Time-Dependent Adaptations To Chronic Exercise In Mice, Jidong Liu, Fang Xiao, Abhinav Choubey, Udhaya Kumar S, Yanxiang Wang, Sungguan Hong, Tingting Yang, Husniye Gul Otlu, Ege Sanem Oturmaz, Emanuele Loro, Yuxiang Sun, Pradip Saha, Tejvir S Khurana, Li Chen, Xinguo Hou, Zheng Sun

Center on Aging Staff Publications

The best time of the day for chronic exercise training and the mechanism underlying the timing effects is unclear. Here, we show that low-intensity, low-volume treadmill training in mice before sleep yields greater benefits than after waking for muscle contractile performance and systemic glucose tolerance. Baseline muscle performance also exhibits diurnal variations, with higher strength but lower endurance before sleep than after waking. Muscle-specific knockout of circadian clock genes Rev-erbα/β (Rev-MKO) in male mice eradicates the diurnal variations in both training and baseline conditions without affecting muscle mass, mitochondrial content, food intake, or spontaneous activities. Multi-omics and metabolic measurements reveal …

Development And Diversity Of Astrocytes, Michael R Williamson, Sanjana Murali, Benjamin Deneen

Faculty, Staff and Students Publications

Proper development of the central nervous system (CNS) depends on astrocytes, which are the most abundant glial cells in the CNS. Here, we provide an overview of astrocyte ontogeny and morphogenesis, highlighting mechanisms that regulate astrocyte development. In addition, we describe the roles of astrocytes in regulating the development of other CNS cell types, with emphasis on neural circuits and vascular networks. We also discuss evidence for astrocyte diversity and its implications for CNS development. Finally, we pose open questions related to astrocyte development and its intersection with astrocyte diversity.

Non-Invasive Tools For Analysis Of Plasma Membrane Protein Topology In Living Cells, Daria Savenkova, Leysan Bulatova, Vera Skripova, Ramziya Kiyamova, Mikhail Bogdanov

Faculty, Staff and Student Publications

Membrane protein topology studies offer guidance to membrane protein structure, folding, and function, serving as a credible scaffold for designing site-directed mutagenesis and biochemical experiments, helping to identify functionally significant extracellular and intracellular regions, modeling three-dimensional structures, and building reliable mechanistic models. Membrane protein structure as a function of given lipid composition and physiological state of the cell is best probed in whole intact cells. A described simple and advanced immunofluorescence protocol applied to the transmembrane orientation of extramembrane domains permits a topology analysis of plasma membrane proteins in their native state in living unperturbed eucaryotic cells. The accessibility of …

Long Akap18 Isoforms Anchor Ubiquitin Specific Proteinases And Coordinate Calcium Reuptake At The Sarcoplasmic Reticulum, Taeyeop Park, Katherine Forbush, Yong Li, Oscar Vivas, Kacey J Rosenthal, Jerome Falcone, Cassandra J Wong, James E Bruce, Claudia Moreno, Carmen W Dessauer, John D Scott

Faculty, Staff and Student Publications

Subcellular targeting of signaling enzymes influences where and when various modes of intracellular communication operate. Macromolecular complexes of signal transduction and signal termination elements favor reversible control of repetitive processes. This includes adrenergic stimulation of excitation–contraction coupling in the heart. Long isoforms of A-kinase anchoring protein 18 (AKAP18γ and δ) modulate this process via regulation of calcium uptake into the sarcoplasmic reticulum through the Ca2+ATPase 2a (SERCA2a). AKAP18 proximity-proteomic screening in cardiomyocytes identifies networks for protein kinase A (PKA) and ubiquitin-specific proteinases (USPs). A 2′phosphoesterase domain on AKAP18 interfaces with the USP4 isoform at the Z bands of sarcomeres. PKA …

Myh11 Rare Variant Augments Aortic Growth And Induces Cardiac Hypertrophy And Heart Failure With Pressure Overload, Zhen Zhou, Kgosi Hughes, Nisha Saif, Hyoseon Kim, Michael P Massett, Mingjie Zheng, Alana C Cecchi, Dongchuan Guo, David R Murdock, Ping Pan, Jelita S Clinton, Jun Wang, John M Greally, Dianna M Milewicz

Faculty, Staff and Student Publications

Smooth muscle cell-specific myosin heavy chain, encoded by MYH11, is selectively expressed in smooth muscle cells (SMCs). Pathogenic variants in MYH11 predispose to a number of disorders, including heritable thoracic aortic disease associated with patent ductus arteriosus, visceral myopathy, and megacystis-microcolon-intestinal hypoperistalsis syndrome. Rare variants of uncertain significance occur throughout the gene, including MYH11 p.Glu1892Asp, and we sought to determine if this variant causes thoracic aortic disease in mice. Genomic editing was used to generate Myh11E1892D/E1892D mice. Wild-type (WT) and mutant mice underwent cardiovascular phenotyping with and without transverse aortic constriction (TAC). Myh11E1892D/E1892D and WT mice displayed …

Targeting Cdk2 And Other Novel Cell Cycle Targets For Breast Cancer Therapy, Mei-Kuang Chen, Linjie Luo, Nicole Massoumi, Khandan Keyomarsi

Faculty, Staff and Student Publications

Introduction: The dysregulation of cyclin-dependent kinases (CDKs) is a key driver of cancer progression, making them attractive therapeutic targets. In CDK4/6 inhibitor (CDK4/6i)-resistant breast cancer, targeting CDK2 offers a promising approach. CDK2 is frequently hyperactivated due to cyclin E1 overexpression or retinoblastoma protein loss, acting as a mechanism that sustains proliferation despite CDK4/6 inhibition. CDK2 inhibitors (CDK2i) show strong anti-tumor activity, particularly in combination with CDK4/6i or immune checkpoint inhibitors.

Areas covered: This review explores the biological roles of CDK2 and its regulatory mechanisms. The review highlights the latest advancements in CDK2i, their mechanisms of action, and their potential in …