Medical Molecular Biology Commons^™

Cyclin C Is Sufficient For Myoblast Differentiation-Induced Mitochondrial Fragmentation, Alicia N. Campbell, Randy Strich

Stratford Campus Research Day

One of the largest and most dynamic tissues in the body, skeletal muscle, requires constant regeneration and upkeep. Dysregulation of this regeneration process has been implicated in many neuromuscular diseases and myotonic dystrophies. Regeneration requires the differentiation of myogenic lineages including exiting the cell cycle, gene expression changes, and fusing of myoblasts into multinucleate myotubes. Part of this reconstruction requires the breakdown and repopulation of mitochondrial networks. At the early onset of myoblast differentiation, there is an upregulation of dynamin-related protein, Drp1, and an increase in mitophagy mediated by sequestosome (SQSTM1) removal of mitochondria.

Previously, our lab has shown that …

Modeling The Role Of Cyclin C In Connecting Stress-Induced Mitochondrial Fission To Apoptosis, Steven J. Doyle, Randy Strich

Stratford Campus Research Day

For normal cell function, exogenous signals must be correctly interpreted, and the proper response executed. The mitochondria are key regulatory nodes of cellular fate. For example, mitochondria undergo fission and fusion cycles depending on the energetic needs of the cell. Additionally, regulated cell death pathways also function at the mitochondria. Cyclin C is a transcriptional regulator of stress response and growth control genes. Following stress, a portion of cyclin C translocates to the cytoplasm, where it interacts with both the mitochondrial fission and apoptotic machinery. Based on these findings, we hypothesize that Cyclin C represents a key mediator linking transcription …

Conservation And Divergence In The Heterochronic Pathway Of C. Elegans And C. Briggsae, Maria Ivanova, Eric G. Moss

Stratford Campus Research Day

The heterochronic pathway of Caenorhabditis elegans is exemplary as a mechanism of developmental timing: mutations in genes of this pathway alter the relative timing of diverse developmental events independent of spatial or cell type specific regulation. It is the most thoroughly characterized developmental timing pathway known. Most of the heterochronic genes are conserved across great evolutionary time, and a few homologs seem to have developmental timing roles in certain contexts. The degree to which other organisms have explicit developmental timing mechanisms, and what factors comprise those mechanisms, isn’t generally known.

Developmental pathways evolve even if the resulting morphology remains the …

Effect Of Uracil Dna Glycosylase Activity On The Efficacy Of Thymidylate Synthase Inhibitor/Hdac Inhibitor Combination Therapies In Colon Cancer, Rashmi Kulkarni, Brian P Weiser

Stratford Campus Research Day

Human uracil DNA glycosylase (UNG2) is responsible for removing uracil bases from DNA and initiates base excision repair pathways. Accumulation of uracil or its fluorinated analogs in DNA is one of the killing mechanisms of thymidylate synthase (TS) inhibitors in cancer cells, and depletion of UNG2 often enhances the toxicity of these anticancer drugs. We tested the effect of UNG2 KO on the efficacy of multiple TS inhibitors (5-fluorouracil, fluorodeoxyuridine, and pemetrexed) and we determined that, except for 5-fluorouracil, all other TS inhibitors were significantly more potent in UNG2 KO cells compared to wild-type HT29 cells. Interestingly, UNG2 protein levels …

Substrate-Specific Effect On Sirtuin Conformation And Oligomerization, Jie Yang, Shannon L. Dwyer, Nathan I. Nicely, Brian P. Weiser

Stratford Campus Research Day

Human sirtuins are a family of nicotinamide adenine dinucleotide (NAD +)-dependent enzymes that are responsible for removing acyl modifications from lysine residues. Sirtuins are involved in the formation and proliferation of cancers and are thought to regulate the progression of neurodegenerative diseases. Although sirtuins can be pharmacologically targeted by small molecules, it is not easy to modulate the substrate selectivity of sirtuins despite the chemical diversity of their substrates. Here, we report substrate-specific effects on sirtuin conformation and oligomerization that regulate enzyme deacylase activity. We used fluorescent acyl peptide probes to study substrate interactions with two sirtuin isoforms: SIRT2 and …

Safety And Efficacy Of Silver-Coated Biomaterials In Vivo, Megan Klem, Darien L. Seidman, Rahyan Mahmoud, Manuella Adu, Lei Yu, Jeffrey Hettinger, Renee M Demarest

Stratford Campus Research Day

Overtreatment and overuse of antibiotics in healthcare and agricultural settings have contributed to the selective pressure on bacterial strains to develop resistance. Resistance can develop as a result of mutations and subsequent resistance genes that allow bacteria to survive against antibiotics. Novel silver-oxide coatings were developed and were previously demonstrated to prevent adhesion of gram-negative bacteria (Escherichia Coli and Pseudomonas Aeruginosa) to the disc, but did not prevent gram-positive bacterial adherence (Streptococcus Aureus). In order to determine whether the silver-oxide coatings are bacterial static and may be preventing progression to biofilm formation, in vivo analysis of S. Aureus attached to …

The Brodmann Area 39/40 Of The Brain In Alzheimer’S, Mild Cognitive Impairment, And No Cognitive Impairment Subjects At Advanced Age Demonstrate Comparable Levels Of Blood-Brain Barrier Breach, Dhara Rana, Forum Mangrola, Randel L. Swanson, Venkat Venkataraman, David A. Bennett, Zoe Arvanitakis, David Libon, Robert Nagele, Nimish Acharya

Stratford Campus Research Day

• Alzheimer’s disease (AD) is one of the most common form of dementia

• Mild cognitive impairment (MCI), specifically amnestic subtype, more likely to progress to AD

• Pathogenesis Theories:

• o Accumulation of amyloid-beta peptides and neurofibrillary tangles containing hyperphosphorylated neuronal tau protein
• o Blood Brain Barrier (BBB) dysfunction is associated with AD pathogenesis

• Brodmann area 39/40: regions of parietal cortex are responsible for language, spatial cognition, memory retrieval, attention, phonological processing, and emotional processing

• Hypothesis: An increased BBB permeability in Brodmann area 39/40 of AD and age-matched MCI and no cognitive impairment (NCI) subjects

Ung2 And Rpa Activity On Ssdna-Dsdna Junctions, Kathy Chen, Sharon Greenwood, Brian P. Weiser

Stratford Campus Research Day

Uracil DNA glycosylase, or UNG2, is an enzyme that is involved in DNA repair. Its primary job is to eliminate harmful uracil bases from DNA strands. To do this, the enzyme is assisted by replication protein A (RPA). RPA helps UNG2 in the identification of uracil bases by targeting UNG2 activity near ssDNA-dsDNA junctions (1-3). The results from assays presented here agree with published findings that showed UNG2 is heavily targeted by RPA to uracil bases that are close to ssDNA-dsDNA junctions (for example, uracil located 9 bps from the junction as opposed to 33 bps) (1,2). However, these previous …

Cdk8 Kinase Module Modifies Expression Of Specific Translation-Related Proteins Before And After Stress, Brittany Friedson, Katrina Cooper

Stratford Campus Research Day

Translation is tightly coupled to growth status. Efficient protein synthesis is necessary for cell growth in nutrient rich environments, while global translation inhibition combined with selective translation of stress-responsive mRNAs helps limit growth in times of stress. Environmental stress cues which inhibit the nutrient-sensing complex TORC1 are known to reduce general translation, but how does the cell alter protein synthesis machinery to adapt to these conditions? A few mechanisms to promote cell survival in nitrogen starvation include post-translational modification and selective degradation of specific mRNA-binding translation factors, as well as inhibition of activators of genes whose products are required for …

Diagnostic Accuracy Of Macular Thickness Map And Texture En Face Images For Detecting Glaucoma In Eyes With Axial High Myopia, Christopher Bowd, Akram Belghith, Jasmin Rezapour, Mark Christopher, Leslie Hyman, Jost B Jonas, Robert N Weinreb, Linda M Zangwill

Wills Eye Hospital Papers

Purpose: To evaluate the diagnostic accuracy of a novel optical coherence tomography texture-based en face image analysis (SALSA-Texture) that requires segmentation of only 1 retinal layer for glaucoma detection in eyes with axial high myopia, and to compare SALSA-Texture with standard macular ganglion cell-inner plexiform layer (GCIPL) thickness, macular retinal nerve fiber layer (mRNFL) thickness, and ganglion cell complex (GCC) thickness maps.

Design: Comparison of diagnostic approaches.

Methods: Cross-sectional data were collected from 92 eyes with primary open-angle glaucoma (POAG) and 44 healthy control eyes with axial high myopia (axial length >26 mm). Optical coherence tomography texture en face images, …

Applying Mci-062, A Novel Pan-Ras Inhibitor, To Treat Kras-Mutant Lung Cancer., Richard Fu

Poster Presentations

Honors thesis poster presentation.

RAS, one of the most prevalent oncogenes, is mutated in 27% of human cancers. Gainof- function RAS mutations activate multiple downstream pathways, including the RASRAF- MEK-ERK and PI3K/AKT/mTOR pathways, which are critical in tumorigenesis and cancer cell proliferation. The RAS proteins KRAS, HRAS, and NRAS along with their downstream effectors are attractive targets for cancer therapy since they act as frequent drivers in lung, colorectal, and pancreatic cancers. However, RAS proteins have relatively smooth surfaces that lack traditional binding pockets, making inhibitors specific to RAS difficult to create. Recently, a novel small molecule pan-RAS inhibitor named …

Applying Mci-062, A Novel Pan-Ras Inhibitor, To Treat Kras-Mutant Lung Cancer, Richard Fu

Undergraduate Theses

RAS is a prevalent oncogene that is mutated in 27% of human cancers. Gain-of-function RAS mutations activate multiple downstream pathways, including the RAS-RAF-MEK-ERK and PI3K/AKT/mTOR pathways, which are critical in tumorigenesis and cancer cell proliferation. RAS proteins such as KRAS, a member of the RAS protein family, and their downstream effectors are attractive targets for cancer therapy since their mutations act as frequent drivers in lung, colorectal, and pancreatic cancers. However, RAS proteins have relatively smooth surfaces that lack traditional binding pockets, making inhibitors specific to RAS difficult to create. Recently, a novel small molecule pan-RAS inhibitor named MCI-062 was …

Crispr-Cas In The Field Of Dentistry: A Comprehensive Collection Of The Potential Uses Of Crispr-Cas9 In Dental Health Care, Lexi Elaine Bales

Chancellor’s Honors Program Projects

No abstract provided.

Heterozygous Frameshift Variants In Hnrnpa2b1 Cause Early-Onset Oculopharyngeal Muscular Dystrophy, Hong Joo Kim, Payam Mohassel, Sandra Donkervoort, Lin Guo, Kevin O'Donovan, Maura Coughlin, Xaviere Lornage, Nicola Foulds, Simon R Hammans, A Reghan Foley, Charlotte M Fare, Alice F Ford, Masashi Ogasawara, Aki Sato, Aritoshi Iida, Pinki Munot, Gautam Ambegaonkar, Rahul Phadke, Dominic G O'Donovan, Rebecca Buchert, Mona Grimmel, Ana Töpf, Irina T Zaharieva, Lauren Brady, Ying Hu, Thomas E Lloyd, Andrea Klein, Maja Steinlin, Alice Kuster, Sandra Mercier, Pascale Marcorelles, Yann Péréon, Emmanuelle Fleurence, Adnan Manzur, Sarah Ennis, Rosanna Upstill-Goddard, Luca Bello, Cinzia Bertolin, Elena Pegoraro, Leonardo Salviati, Courtney E French, Andriy Shatillo, F Lucy Raymond, Tobias B Haack, Susana Quijano-Roy, Johann Böhm, Isabelle Nelson, Tanya Stojkovic, Teresinha Evangelista, Volker Straub, Norma B Romero, Jocelyn Laporte, Francesco Muntoni, Ichizo Nishino, Mark A Tarnopolsky, James Shorter, Carsten G Bönnemann, J Paul Taylor

Department of Biochemistry and Molecular Biology Faculty Papers

Missense variants in RNA-binding proteins (RBPs) underlie a spectrum of disease phenotypes, including amyotrophic lateral sclerosis, frontotemporal dementia, and inclusion body myopathy. Here, we present ten independent families with a severe, progressive muscular dystrophy, reminiscent of oculopharyngeal muscular dystrophy (OPMD) but of much earlier onset, caused by heterozygous frameshift variants in the RBP hnRNPA2/B1. All disease-causing frameshift mutations abolish the native stop codon and extend the reading frame, creating novel transcripts that escape nonsense-mediated decay and are translated to produce hnRNPA2/B1 protein with the same neomorphic C-terminal sequence. In contrast to previously reported disease-causing missense variants in HNRNPA2B1, these frameshift …

A Periplasmic Cinched Protein Is Required For Siderophore Secretion And Virulence Of Mycobacterium Tuberculosis., Lei Zhang, James E Kent, Meredith Whitaker, David C Young, Dominik Herrmann, Alexander E Aleshin, Ying-Hui Ko, Gino Cingolani, Jamil S Saad, D Branch Moody, Francesca M Marassi, Sabine Ehrt, Michael Niederweis

Department of Biochemistry and Molecular Biology Faculty Papers

Iron is essential for growth of Mycobacterium tuberculosis, the causative agent of tuberculosis. To acquire iron from the host, M. tuberculosis uses the siderophores called mycobactins and carboxymycobactins. Here, we show that the rv0455c gene is essential for M. tuberculosis to grow in low-iron medium and that secretion of both mycobactins and carboxymycobactins is drastically reduced in the rv0455c deletion mutant. Both water-soluble and membrane-anchored Rv0455c are functional in siderophore secretion, supporting an intracellular role. Lack of Rv0455c results in siderophore toxicity, a phenotype observed for other siderophore secretion mutants, and severely impairs replication of M. tuberculosis in mice, demonstrating …

Investigating The Efficacy Of Tazemetosttat For In Vitro Treatment Of Human Triple Negative Breast Cancer Cells, Harshita Indukuri

Honors Scholars Collaborative Projects

Cancer is a formidable, genetic disease that affects many people, either directly or indirectly. Breast cancer is the most commonly diagnosed cancer worldwide (31). Triple-negative breast cancer (TNBC) is a type of breast cancer that has a higher lethality compared to other breast cancers and has a poor prognosis due to its highly invasive nature and limited treatment options. Finding safe, effective, and accessible treatment for TNBC is integral to treating TNBC patients. Tazemetostat is an EZH2-inhibitor that has recently been approved for use in epithelioid sarcoma (23). EZH2 is an overexpressed protein in many cancers, including TNBC (11). However, …

Aryl Hydrocarbon Receptor Regulation Of Induction Of Inflammatory Mediators By Organic Dust Extract In Lung Epithelial Cells, Maxine Stenhouse

Biotechnology Theses

Previous studies have indicated a link between respiratory symptoms and diseases and organic dust exposure in agricultural workers. The aryl hydrocarbon receptor (AhR), a transcription factor activated by a wide variety of exogenous and endogenous compounds, is known to be involved in the metabolism of toxic chemicals and recently in the modulation of immune and inflammatory responses. To better understand mechanisms of pathogenesis of respiratory symptoms and diseases, the role of AhR in the regulation of induction of inflammatory mediators by poultry organic dust extract in airway epithelial cells was studied. The role of AhR was studied by investigating the …

Functions Of Adp-Ribose Transferases In The Maintenance Of Telomere Integrity, Daniela Muoio, Natalie Laspata, Elise Fouquerel

Department of Biochemistry and Molecular Biology Faculty Papers

The ADP-ribose transferase (ART) family comprises 17 enzymes that catalyze mono- or poly-ADP-ribosylation, a post-translational modification of proteins. Present in all subcellular compartments, ARTs are implicated in a growing number of biological processes including DNA repair, replication, transcription regulation, intra- and extra-cellular signaling, viral infection and cell death. Five members of the family, PARP1, PARP2, PARP3, tankyrase 1 and tankyrase 2 are mainly described for their crucial functions in the maintenance of genome stability. It is well established that the most describedrole of PARP1, 2 and 3 is the repair of DNA lesions while tankyrases 1 and 2 are crucial …

In-Silico Determination Of Phytochemicals Against Spike Protein Of Covid-19, Muhammad Irfan, Muhammad Adil, Areej Fatima, Arooj Fatima, Ammara Khalid, Muhammad Bilal

Journal of Bioresource Management

Spike protein is present on the exterior of SARS-CoV-2 that mediates the binding of virus with human ACE2 receptor. S-protein has the ability to mutate in a short span of time. Using S-protein as a therapeutic target, Covid-19 infection can be prevented. Many plant-derived phytochemicals are found effective to treat viral infections. In this study, we selected top 10 phytochemicals following the Lipinski’s rule of five from total 82 candidate phytochemicals. The binding energies were determined through molecular docking of the phytochemical ligands. Top three compounds having maximal interactions and lowest binding energies were visualized. We suggested Dictamnine, Deoxypodophyllotoxin and …

Mechanisms Of Mitochondrial Promoter Recognition In Humans And Other Mammalian Species, Angelica Zamudio-Ochoa, Yaroslav I Morozov, Azadeh Sarfallah, Michael Anikin, Dmitry Temiakov

Department of Biochemistry and Molecular Biology Faculty Papers

Recognition of mammalian mitochondrial promoters requires the concerted action of mitochondrial RNA polymerase (mtRNAP) and transcription initiation factors TFAM and TFB2M. In this work, we found that transcript slippage results in heterogeneity of the human mitochondrial transcripts in vivo and in vitro. This allowed us to correctly interpret the RNAseq data, identify the bona fide transcription start sites (TSS), and assign mitochondrial promoters for > 50% of mammalian species and some other vertebrates. The divergent structure of the mammalian promoters reveals previously unappreciated aspects of mtDNA evolution. The correct assignment of TSS also enabled us to establish the precise register of …