Amino Acids, Peptides, and Proteins Commons^™

Selective Deletion Of Slc2a1 From The Rpe Reveals That Rods But Not Cones Depend On Glucose Transport Across The Outer Blood-Retinal Barrier, Lauren L. Daniele, John Y.S. Han, Minzhong Yu, Ravi A. Sangani, Craig D. Beight, Cyrus Rostami, Philip D. Kiser, Neal S. Peachy, Nancy J. Philp

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

GLUT1 facilitates a continuous flow of glucose across the inner and outer blood-retinal barriers (BRBs) to support vision. To understand the extent to which photoreceptors rely on glucose transport across the outer BRB, we generated a tamoxifen-inducible conditional knockout of Slc2a1 in the retinal pigment epithelium (RPE) (RPE-iΔGlut1). In the RPE-iΔGlut1 mice, rod photoreceptors exhibited impaired outer segment renewal and decreased the expression of proteins involved in phototransduction and ciliary transport. Proteins regulating the retinal stress response increased. Cone photoreceptors were functional and viable 15 months post-tamoxifen treatment in the RPE-iΔGlut1 mice, while 70% of the rods died. …

Increased Intermembrane Space [Ca2+] Drives Mitochondrial Structural Damage In Cpvt, Shanna Hamilton, Radmila Terentyeva, Roland Veress, Fruzsina Perger, Zuzana Nichtova, Mark Bannister, Jinxi Wang, Sage Quiggle, Rachel Battershell, Matthew Gorr, Sandor Györke, Bum-Rak Choi, Christopher George, Andriy Belevych, György Csordás, Dmitry Terentyev

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Mitochondrial dysfunction caused by abnormally high RyR2 (ryanodine receptor) activity is a common finding in cardiovascular diseases. Mechanisms linking RyR2 gain of function with mitochondrial remodeling remain elusive. We hypothesized that RyR2 hyperactivity in cardiac disease increases [Ca 2+ ] in the mitochondrial intermembrane space (IMS) and activates the Ca 2+ -sensitive protease calpain, driving remodeling of mitochondrial cristae architecture through cleavage of structural protein OPA1 (optic atrophy protein 1).

METHODS: We generated a highly arrhythmogenic rat model of catecholaminergic polymorphic ventricular tachycardia, induced by RyR2 gain-of-function mutation S2236L(Ser2336Leu)(+/-) . We created a new biosensor to measure IMS-[Ca2+ ] …

Discovery Of A Small Molecule Tlr3 Agonist Adjuvant, Branden Lee, Danica Dong, Etsuro Nanishi, John Mark Awad, Kimia Abedi, Yoshine Saito, Francesco Borriello, Soumik Barman, Byron Brook, Aisling Kelly, Manisha Menon, Constance Marques-Mourlet, Maansi Gupta, Ida Lister, Chiwoo Oh, Kevin Lyskawa, Morgan Goetz, Kristina Walker, Wing Ki Cheng, Spencer Brightman, Pankaj Sharma, Timothy O'Meara, Katherine Chew, Daniel Vieira, Kevin Ryff, Cali Sweitzer, Sanya Thomas, Simon Van Haren, Matthew Pettengill, Hyuk-Soo Seo, Sirano Dhe-Paganon, Wei Zhang, Ofer Levy, David Dowling

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Pattern-recognition receptor (PRR) agonists are valuable agents across multiple medical applications, from vaccinology to immune-oncology. However, well-defined and potent small molecule agonists for many PRRs still await discovery and development. Screening of chemical libraries of ~200,000 small molecules for maturation of human monocytic cells by quantifying NF-κB activation and cell adherence was completed. From this screen, we selected a thiazole benzamide derivative, PVP-057, for its robust immunomodulatory properties, low toxicity profile, and concentration-dependent activity. In vitro investigation of pathway and receptor activation reveals that PVP-057 is a Toll-like receptor 3 (TLR3) agonist. As a single-component adjuvant, administered intramuscularly or intradermally …

Runx2 Cooperates With Srebp1 To Rewire Cancer Metabolism And Promote Aggressiveness, Emanuele Vitale, Mila Gugnoni, Veronica Manicardi, Silvia Muccioli, Federica Torricelli, Benedetta Donati, Simonetta Piana, Gloria Manzotti, Elisa Salviato, Francesca Reggiani, Cristian Ascione, Rebecca Vezzani, Moira Ragazzi, Mattia Forcato, Oriana Romano, Silvio Bicciato, Aaron Goldman, Marco Tigano, Alessia Ciarrocchi

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Embryonic Transcription Factors (TFs) are often reactivated in cancer, driving developmental gene programs that support phenotypic plasticity. Metabolic adaptation fuels this plasticity by supplying energy and molecular building blocks for growth. RUNX2, the master regulator of bone morphogenesis, is ectopically expressed in epithelial cancer, promoting metastasis through trans-differentiation processes like Epithelial-to-Mesenchymal Transition (EMT) and osteomimicry. By combining omics data with functional validation, we demonstrated that RUNX2 drives cancer cell metabolic rewiring by repressing mitochondrial respiration while promoting anabolic processes. We showed that RUNX2 upregulates key genes of lipid biosynthesis by regulating and cooperating with SREBP1. In vivo expression analysis in …

Uncovering The Pml::Rara Fusion In Cytogenetically Cryptic And Fish-Negative Acute Promyelocytic Leukemia-A Case Report And Comprehensive Literature Review, Busra Delikkaya, Jaime Eberle-Singh, Arianna Morton, Jerald Gong, Jinglan Liu

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The PML::RARA fusion resulting from t(15;17) is the genetic hallmark of acute promyelocytic leukemia (APL), typically detected by cytogenetics and/or fluorescence in situ hybridization (FISH) studies. Rarely, APL patients present with normal cytogenetics and FISH findings, complicating diagnosis and delaying life-saving therapy. We report a 23-year-old male with clinical, morphologic and immunophenotypic features consistent with APL but negative for FISH studies. Despite prompt initiation of all-trans retinoic acid (ATRA) based on clinical suspicion, the patient succumbed to intracranial hemorrhage. Quantitative reverse transcriptase PCR (qRT-PCR) confirmed a long isoform PML::RARA fusion. A review of 34 published cytogenetics- and FISH-negative cases since …

Distinct Transcriptional Regulation Of The Wnt And Tgfβ Signaling Families Associated With Wound Healing And Fibrotic Outcomes To Lens Injury, Catherine Lalman, Kylie R. Stabler, Joshua Disatham, Lisa A. Brennan, Marc Kantorow, Janice L. Walker

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Posterior capsule opacification (PCO) is a fibrotic complication of cataract surgery caused by aberrant repair of residual lens cells. It remains unclear how the lens injury response shifts toward a pathological repair process. Here, we performed a transcriptional analysis of two major pro-fibrotic pathways, the TGF-β superfamily and Wnt signaling pathways to determine how they are differentially regulated during regenerative wound healing versus fibrosis in a lens injury model. For these studies, RNA sequencing was performed on an ex vivo lens explant system that models post-surgical healing within regenerative and fibrotic microenvironments, from 0 to 3 days post-injury. Fibrotic conditions …

Rescue Of The First Mitochondrial Membrane Carrier, The Mpic, By Tat-Mediated Protein Replacement Treatment, Samar Zabit, Orly Melloul, Michal Lichtenstein, Erin L. Seifert, Haya Lorberboum-Galski

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

The mitochondrial phosphate carrier (mPiC), encoded by the nuclear gene SLC25A3, is synthesized with an N-terminus mitochondrial targeting sequence (MTS), enabling its import into the mitochondria. mPiC imports inorganic phosphate (P_i) into the mitochondrial matrix for ATP production and other matrix phosphorylation reactions, as well as regulates mitochondrial Ca²⁺ uptake and buffering of matrix Ca²⁺. PiC also imports copper (Cu), crucial to COX subunit holoenzyme assembly. Variants in SLC25A3 exist and lead to mPiC deficiency (MPCD), cause a rare autosomal recessive disease with no current cure; patients with MPCD usually die within the first …

Vdac2 And Bak Scarcity In Liver Mitochondria Enables Targeting Hepatocarcinoma While Sparing Hepatocytes, Shamim Naghdi, Piyush Mishra, Soumya S. Roy, David Weaver, Ludivine Walter, Erika Davies, Anil N. Antony, Xuena Lin, Gisela Moehren, Mark A. Feitelson, Christopher A. Reed, Tullia Lindsten, Craig B. Thompson, Hien T. Dang, Jan B. Hoek, Erik S. Knudsen, György Hajnóczky

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Differences between normal tissues and invading tumors that allow tumor targeting while saving normal tissue are much sought after. Here we show that scarcity of VDAC2, and the consequent lack of Bak recruitment to mitochondria, renders hepatocyte mitochondria resistant to permeabilization by truncated Bid (tBid), a Bcl-2 Homology 3 (BH3)-only, Bcl-2 family protein. Increased VDAC2 and Bak is found in most human liver cancers and mitochondria from tumors and hepatic cancer cell lines exhibit VDAC2- and Bak-dependent tBid sensitivity. Exploring potential therapeutic targeting, we find that combinations of activators of the tBid pathway with inhibitors of the Bcl-2 family proteins …

Nuclear Expression Of Dynamin 2 Is Associated With Tumor Aggressiveness In Bladder Cancer Patients: A Bioinformatics And Experimental Approach, Mahdieh Razmi, Leili Saeednejad Zanjani, Mandana Rahimi, Roya Sajed, Sadegh Safaei, Zahra Madjd, Roya Ghods

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

BACKGROUND: Dynamin 2 (DNM2) is aberrantly expressed in different malignancies and exerts a function in tumor progression.

AIMS: This study, for the first time, aimed to evaluate the clinical and prognostic value of DNM2 in the pathophysiology of bladder cancer using bioinformatics analysis and experimental evaluation.

METHODS AND RESULTS: We analyzed gene expression of DNM2 in bladder tumor by GEPIA2 and GENT2 platforms. Cluster subnetworks were recognized from the protein-protein interaction (PPI) network using the MCODE plugin to screen the key genes. Subsequently, the pathway enrichment analysis was evaluated. Then, the immunohistochemical examination was conducted on 209 paraffin-embedded bladder cancer …

Opa1 And Disease-Causing Mutants Perturb Mitochondrial Nucleoid Distribution, J. Macuada, I. Molina-Riquelme, G. Vidal, N. Pérez-Bravo, C. Vásquez-Trincado, G. Aedo, D. Lagos, P. Yu-Wai-Man, R. Horvath, T. J. Rudge, B. Cartes-Saavedra, V. Eisner

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Optic atrophy protein 1 (OPA1) mediates inner mitochondrial membrane (IMM) fusion and cristae organization. Mutations in OPA1 cause autosomal dominant optic atrophy (ADOA), a leading cause of blindness. Cells from ADOA patients show impaired mitochondrial fusion, cristae structure, bioenergetic function, and mitochondrial DNA (mtDNA) integrity. The mtDNA encodes electron transport chain subunits and is packaged into nucleoids spread within the mitochondrial population. Nucleoids interact with the IMM, and their distribution is tightly linked to mitochondrial fusion and cristae shaping. Yet, little is known about the physio-pathological relevance of nucleoid distribution. We studied the effect of OPA1 and ADOA-associated mutants on …