Medical Cell Biology Commons^™

Protein Translation Paradox: Implications In Translational Regulation Of Aging, Harper S Kim, Andrew M Pickering

Faculty, Staff and Student Publications

Protein translation is an essential cellular process playing key roles in growth and development. Protein translation declines over the course of age in multiple animal species, including nematodes, fruit flies, mice, rats, and even humans. In all these species, protein translation transiently peaks in early adulthood with a subsequent drop over the course of age. Conversely, lifelong reductions in protein translation have been found to extend lifespan and healthspan in multiple animal models. These findings raise the protein synthesis paradox: age-related declines in protein synthesis should be detrimental, but life-long reductions in protein translation paradoxically slow down aging and prolong …

Loss Of Ubiquitin-Specific Peptidase 18 Destabilizes 14-3-3Ζ Protein And Represses Lung Cancer Metastasis, Zibo Chen, Lin Zheng, Yulong Chen, Xiuxia Liu, Masanori Kawakami, Lisa Maria Mustachio, Jason Roszik, Katherine V Ferry-Galow, Ralph E Parchment, Xin Liu, Thorkell Andresson, Gerard Duncan, Jonathan M Kurie, Jaime Rodriguez-Canales, Xi Liu, Ethan Dmitrovsky

Faculty, Staff and Student Publications

Cancer metastasis is a major cause of cancer-related mortality. Strategies to reduce metastases are needed especially in lung cancer, the most common cause of cancer mortality. We previously reported increased ubiquitin-specific peptidase 18 (USP18) expression in lung and other cancers. Engineered reduction of USP18 expression repressed lung cancer growth and promoted apoptosis. This deubiquitinase (DUB) stabilized targeted proteins by removing the complex interferon-stimulated gene 15 (ISG15). This study explores if the loss of USP18 reduced lung cancer metastasis. USP18 knock-down in lung cancer cells was independently achieved using small hairpin RNAs (shRNAs) and small interfering RNAs (siRNAs). USP18 knock-down reduced …

Clinical Significance Of Glycolytic Metabolic Activity In Hepatocellular Carcinoma, Joann Jung, Sowon Park, Yeonwoo Jang, Sung-Hwan Lee, Yun Seong Jeong, Sun Young Yim, Ju-Seog Lee

Faculty, Staff and Student Publications

High metabolic activity is a hallmark of cancers, including hepatocellular carcinoma (HCC). However, the molecular features of HCC with high metabolic activity contributing to clinical outcomes and the therapeutic implications of these characteristics are poorly understood. We aimed to define the features of HCC with high metabolic activity and uncover its association with response to current therapies. By integrating gene expression data from mouse liver tissues and tumor tissues from HCC patients (n = 1038), we uncovered three metabolically distinct HCC subtypes that differ in clinical outcomes and underlying molecular biology. The high metabolic subtype is characterized by poor …

Anti-Cancer Mechanisms Of Action Of Therapeutic Alternating Electric Fields (Tumor Treating Fields [Ttfields]), Shadi Shams, Chirag B Patel

Faculty, Staff and Student Publications

Despite improved survival outcomes across many cancer types, the prognosis remains grim for certain solid organ cancers including glioblastoma and pancreatic cancer. Invariably in these cancers, the control achieved by time-limited interventions such as traditional surgical resection, radiation therapy, and chemotherapy is short-lived. A new form of anti-cancer therapy called therapeutic alternating electric fields (AEFs) or tumor treating fields (TTFields) has been shown, either by itself or in combination with chemotherapy, to have anti-cancer effects that translate to improved survival outcomes in patients. Although the pre-clinical and clinical data are promising, the mechanisms of TTFields are not fully elucidated. Many …

Spatial Heterogeneity Of Infiltrating T Cells In High-Grade Serous Ovarian Cancer Revealed By Multi-Omics Analysis, Bin Yang, Xiong Li, Wei Zhang, Junpeng Fan, Yong Zhou, Wenting Li, Jingjing Yin, Xiaohang Yang, Ensong Guo, Xi Li, Yu Fu, Si Liu, Dianxing Hu, Xu Qin, Yingyu Dou, Rourou Xiao, Funian Lu, Zizhuo Wang, Tianyu Qin, Wei Wang, Qinghua Zhang, Shuaicheng Li, Ding Ma, Gordon B Mills, Gang Chen, Chaoyang Sun

Faculty, Staff and Student Publications

Tumor-infiltrating lymphocytes (TILs), especially CD8+ TILs, represent a favorable prognostic factor in high-grade serous ovarian cancer (HGSOC) and other tumor lineages. Here, we analyze the spatial heterogeneity of different TIL subtypes in HGSOC. We integrated RNA sequencing, whole-genome sequencing, bulk T cell receptor (TCR) sequencing, as well as single-cell RNA/TCR sequencing to investigate the characteristics and differential composition of TILs across different HGSOC sites. Two immune "cold" patterns in ovarian cancer are identified: (1) ovarian lesions with low infiltration of mainly dysfunctional T cells and immunosuppressive Treg cells and (2) omental lesions infiltrated with non-tumor-specific bystander cells. Exhausted CD8 T …

Processing And Cryopreservation Of Human Ureter Tissues For Single-Cell And Spatial Transcriptomics Assays, Emily E Fink, Surbhi Sona, Byron H Lee, Angela H Ting

Faculty, Staff and Student Publications

Characterizing the cellular heterogeneity of human ureter tissues using single-cell RNA sequencing (scRNA-seq) and spatial transcriptomics provides a detailed atlas of cell types, signaling networks, and potential cell-cell cross talk underlying developmental and regenerative pathways. We describe an optimized protocol for generating, cryopreserving, and thawing single-cell suspensions from ureter tissues isolated post-cystectomy for scRNA-seq. In addition, we describe an optimized protocol for cryopreserving human ureter tissues for 10x Genomics Visium spatial gene expression platform. For complete details on the use and execution of this protocol, please refer to Fink et al. (2022).

Defining Cellular Population Dynamics At Single-Cell Resolution During Prostate Cancer Progression, Alexandre A Germanos, Sonali Arora, Ye Zheng, Erica T Goddard, Ilsa M Coleman, Anson T Ku, Scott Wilkinson, Hanbing Song, Nicholas J Brady, Robert A Amezquita, Michael Zager, Annalysa Long, Yu Chi Yang, Jason H Bielas, Raphael Gottardo, David S Rickman, Franklin W Huang, Cyrus M Ghajar, Peter S Nelson, Adam G Sowalsky, Manu Setty, Andrew C Hsieh

Faculty, Staff and Student Publications

Advanced prostate malignancies are a leading cause of cancer-related deaths in men, in large part due to our incomplete understanding of cellular drivers of disease progression. We investigate prostate cancer cell dynamics at single-cell resolution from disease onset to the development of androgen independence in an in vivo murine model. We observe an expansion of a castration-resistant intermediate luminal cell type that correlates with treatment resistance and poor prognosis in human patients. Moreover, transformed epithelial cells and associated fibroblasts create a microenvironment conducive to pro-tumorigenic immune infiltration, which is partially androgen responsive. Androgen-independent prostate cancer leads to significant diversification of …

The Rheumatoid Arthritis Drug Auranofin Lowers Leptin Levels And Exerts Antidiabetic Effects In Obese Mice, Aaron R Cox, Peter M Masschelin, Pradip K Saha, Jessica B Felix, Robert Sharp, Zeqin Lian, Yan Xia, Natasha Chernis, David A Bader, Kang Ho Kim, Xin Li, Jun Yoshino, Xin Li, Gang Li, Zheng Sun, Huaizhu Wu, Cristian Coarfa, David D Moore, Samuel Klein, Kai Sun, Sean M Hartig

Faculty, Staff and Student Publications

Low-grade, sustained inflammation in white adipose tissue (WAT) characterizes obesity and coincides with type 2 diabetes mellitus (T2DM). However, pharmacological targeting of inflammation lacks durable therapeutic effects in insulin-resistant conditions. Through a computational screen, we discovered that the FDA-approved rheumatoid arthritis drug auranofin improved insulin sensitivity and normalized obesity-associated abnormalities, including hepatic steatosis and hyperinsulinemia in mouse models of T2DM. We also discovered that auranofin accumulation in WAT depleted inflammatory responses to a high-fat diet without altering body composition in obese wild-type mice. Surprisingly, elevated leptin levels and blunted beta-adrenergic receptor activity achieved by leptin receptor deletion abolished the antidiabetic …

Temporal And Spatial Metabolite Dynamics Impart Control In Adipogenesis, Kristin Eckel-Mahan

Faculty, Staff and Student Publications

The process of adipogenesis is critical for forming new, healthy adipocytes that are capable of storing lipids. In this issue, Sánchez-Ramírez and Ung et al. (2022. J. Cell Biol. https://doi.org/10.1083/jcb.202111137) reveal a novel role for the metabolite nicotinamide adenine dinucleotide in controlling differentiation of mesenchymal stromal cells into adipocytes.

Blockade Of Fgf2/Fgfr2 Partially Overcomes Bone Marrow Mesenchymal Stromal Cells Mediated Progression Of T-Cell Acute Lymphoblastic Leukaemia, Chen Tian, Yueyang Li, Lina Wang, Junqi Si, Yaxin Zheng, Junnan Kang, Yafei Wang, M James You, Guoguang Zheng

Faculty, Staff and Student Publications

The development of acute lymphoblastic leuakemia (ALL) is partly attributed to the effects of bone marrow (BM) microenvironment, especially mesenchymal stromal cells (MSCs), which interact bilaterally with leukaemia cells, leading to ALL progression. In order to find MSCs-based microenvironment targeted therapeutic strategies, Notch1-induced T-cell ALL (T-ALL) mice models were used and dynamic alterations of BM-MSCs with increased cell viability during T-ALL development was observed. In T-ALL mice derived stroma-based condition, leukaemia cells showed significantly elevated growth capacity indicating that MSCs participated in leukaemic niche formation. RNA sequence results revealed that T-ALL derived MSCs secreted fibroblast growth factor 2 (FGF2), which …

The Tumor Invasion Paradox In Cancer Stem Cell-Driven Solid Tumors, Alexandra Shyntar, Ashna Patel, Meghan Rhodes, Heiko Enderling, Thomas Hillen

Faculty, Staff and Student Publications

Cancer stem cells (CSCs) are key in understanding tumor growth and tumor progression. A counterintuitive effect of CSCs is the so-called tumor growth paradox: the effect where a tumor with a higher death rate may grow larger than a tumor with a lower death rate. Here we extend the modeling of the tumor growth paradox by including spatial structure and considering cancer invasion. Using agent-based modeling and a corresponding partial differential equation model, we demonstrate and prove mathematically a tumor invasion paradox: a larger cell death rate can lead to a faster invasion speed. We test this result on a …

Artificial Intelligence For Radiation Oncology Applications Using Public Datasets, Kareem A Wahid, Enrico Glerean, Jaakko Sahlsten, Joel Jaskari, Kimmo Kaski, Mohamed A Naser, Renjie He, Abdallah S R Mohamed, Clifton D Fuller

Faculty, Staff and Student Publications

Artificial intelligence (AI) has exceptional potential to positively impact the field of radiation oncology. However, large curated datasets - often involving imaging data and corresponding annotations - are required to develop radiation oncology AI models. Importantly, the recent establishment of Findable, Accessible, Interoperable, Reusable (FAIR) principles for scientific data management have enabled an increasing number of radiation oncology related datasets to be disseminated through data repositories, thereby acting as a rich source of data for AI model building. This manuscript reviews the current and future state of radiation oncology data dissemination, with a particular emphasis on published imaging datasets, AI …

Pim1 Promotes Hepatic Conversion By Suppressing Reprogramming-Induced Ferroptosis And Cell Cycle Arrest, Yangyang Yuan, Chenwei Wang, Xuran Zhuang, Shaofeng Lin, Miaomiao Luo, Wankun Deng, Jiaqi Zhou, Lihui Liu, Lina Mao, Wenbo Peng, Jian Chen, Qiangsong Wang, Yilai Shu, Yu Xue, Pengyu Huang

Faculty, Staff and Student Publications

Protein kinase-mediated phosphorylation plays a critical role in many biological processes. However, the identification of key regulatory kinases is still a great challenge. Here, we develop a trans-omics-based method, central kinase inference, to predict potentially key kinases by integrating quantitative transcriptomic and phosphoproteomic data. Using known kinases associated with anti-cancer drug resistance, the accuracy of our method denoted by the area under the curve is 5.2% to 29.5% higher than Kinase-Substrate Enrichment Analysis. We further use this method to analyze trans-omic data in hepatocyte maturation and hepatic reprogramming of human dermal fibroblasts, uncovering 5 kinases as regulators in the two …

Genetic- And Diet-Induced Ω-3 Fatty Acid Enrichment Enhances Trpv4-Mediated Vasodilation In Mice, Rebeca Caires, Tessa A C Garrud, Luis O Romero, Carlos Fernández-Peña, Valeria Vásquez, Jonathan H Jaggar, Julio F Cordero-Morales

Faculty, Staff and Student Publications

TRPV4 channel activation in endothelial cells leads to vasodilation, while impairment of TRPV4 activity is implicated in vascular dysfunction. Strategies that increase TRPV4 activity could enhance vasodilation and ameliorate vascular disorders. Here, we show that supplementation with eicosapentaenoic acid (EPA), an ω-3 polyunsaturated fatty acid known to have beneficial cardiovascular effects, increases TRPV4 activity in human endothelial cells of various vascular beds. Mice carrying the C. elegans FAT-1 enzyme, which converts ω-6 to ω-3 polyunsaturated fatty acids, display higher EPA content and increased TRPV4-mediated vasodilation in mesenteric arteries. Likewise, mice fed an EPA-enriched diet exhibit enhanced and prolonged TRPV4-dependent vasodilation …

Intermediary Role Of Lung Alveolar Type 1 Cells In Epithelial Repair Upon Sendai Virus Infection, Belinda J Hernandez, Margo P Cain, Anne M Lynch, Jose R Flores, Michael J Tuvim, Burton F Dickey, Jichao Chen

Faculty, Staff and Student Publications

The lung epithelium forms the first barrier against respiratory pathogens and noxious chemicals; however, little is known about how more than 90% of this barrier, made of AT1 (alveolar type 1) cells, responds to injury. Using the Sendai virus to model natural infection in mice, we find evidence that AT1 cells have an intermediary role by persisting in areas depleted of AT2 cells, upregulating IFN responsive genes, and receding from invading airway cells. Sendai virus infection mobilizes airway cells to form alveolar SOX2+ (Sry-box 2+) clusters without differentiating into AT1 or AT2 cells. Large AT2 cell-depleted areas remain covered by …

Schwann Cells Induce Phenotypic Changes In Oral Cancer Cells, Maria Daniela Santi, Morgan Zhang, Elizabeth Salvo, Kesava Asam, Chi T Viet, Tongxin Xie, Moran Amit, Bradley Aouizerat, Yi Ye

Faculty, Staff and Student Publications

Head and neck cancer (HNC) is the seventh most common cancer worldwide, the majority being oral squamous cell carcinoma. Despite advances in cancer diagnosis and treatment, the survival rate of patients with HNC remains stagnant. The cancer-nerve interaction has been recognized as an important driver of cancer progression. Schwann cells, a type of peripheral glia, have been implicated in promoting cancer cell growth, migration, dispersion, and invasion into the nerve in many cancers. Here, it is demonstrated that the presence of Schwann cells makes oral cancer cells more aggressive by promoting their proliferation, extracellular matrix breakdown, and altering cell metabolism. …

Structure-Based Design Of Stapled Peptides That Bind Gabarap And Inhibit Autophagy, Hawley Brown, Mia Chung, Alina Üffing, Nefeli Batistatou, Tiffany Tsang, Samantha Doskocil, Weiqun Mao, Dieter Willbold, Robert C Bast, Zhen Lu, Oliver H Weiergräber, Joshua A Kritzer

Faculty, Staff and Student Publications

The LC3/GABARAP family of proteins is involved in nearly every stage of autophagy. Inhibition of LC3/GABARAP proteins is a promising approach to blocking autophagy, which sensitizes advanced cancers to DNA-damaging chemotherapy. Here, we report the structure-based design of stapled peptides that inhibit GABARAP with nanomolar affinities. Small changes in staple structure produced stapled peptides with very different binding modes and functional differences in LC3/GABARAP paralog selectivity, ranging from highly GABARAP-specific to broad inhibition of both subfamilies. The stapled peptides exhibited considerable cytosolic penetration and resistance to biological degradation. They also reduced autophagic flux in cultured ovarian cancer cells and sensitized …

A Method For Bridging Population-Specific Genotypes To Detect Gene Modules Associated With Alzheimer's Disease, Yulin Dai, Peilin Jia, Zhongming Zhao, Assaf Gottlieb

Faculty, Staff and Student Publications

BACKGROUND: Genome-wide association studies have successfully identified variants associated with multiple conditions. However, generalizing discoveries across diverse populations remains challenging due to large variations in genetic composition. Methods that perform gene expression imputation have attempted to address the transferability of gene discoveries across populations, but with limited success.

METHODS: Here, we introduce a pipeline that combines gene expression imputation with gene module discovery, including a dense gene module search and a gene set variation analysis, to address the transferability issue. Our method feeds association probabilities of imputed gene expression with a selected phenotype into tissue-specific gene-module discovery over protein interaction …

Alyref, A Novel Factor Involved In Breast Carcinogenesis, Acts Through Transcriptional And Post-Transcriptional Mechanisms Selectively Regulating The Short Neat1 Isoform, Christiane Klec, Erik Knutsen, Daniela Schwarzenbacher, Katharina Jonas, Barbara Pasculli, Ellen Heitzer, Beate Rinner, Katarina Krajina, Felix Prinz, Benjamin Gottschalk, Peter Ulz, Alexander Deutsch, Andreas Prokesch, Stephan W Jahn, S Mohammad Lellahi, Maria Perander, Raffaela Barbano, Wolfgang F Graier, Paola Parrella, George Adrian Calin, Martin Pichler

Faculty, Staff and Student Publications

The RNA-binding protein ALYREF (THOC4) is involved in transcriptional regulation and nuclear mRNA export, though its role and molecular mode of action in breast carcinogenesis are completely unknown. Here, we identified high ALYREF expression as a factor for poor survival in breast cancer patients. ALYREF significantly influenced cellular growth, apoptosis and mitochondrial energy metabolism in breast cancer cells as well as breast tumorigenesis in orthotopic mouse models. Transcriptional profiling, phenocopy and rescue experiments identified the short isoform of the lncRNA NEAT1 as a molecular trigger for ALYREF effects in breast cancer. Mechanistically, we found that ALYREF binds to the NEAT1 …

Targeting Syndecan-1: New Opportunities In Cancer Therapy, Zecheng Yang, Shuaitong Chen, Haoqiang Ying, Wantong Yao

Faculty, Staff and Student Publications

Syndecan-1 (SDC1, CD138) is one of the heparan sulfate proteoglycans and is essential for maintaining normal cell morphology, interacting with the extracellular and intracellular protein repertoire, as well as mediating signaling transduction upon environmental stimuli. The critical role of SDC1 in promoting tumorigenesis and metastasis has been increasingly recognized in various cancer types, implying a promising potential of utilizing SDC1 as a novel target for cancer therapy. This review summarizes the current knowledge on SDC1 structure and functions, including its role in tumor biology. We also discuss the highlights and limitations of current SDC1-targeted therapies as well as the obstacles …

Dedifferentiation-Mediated Stem Cell Niche Maintenance In Early-Stage Ductal Carcinoma In Situ Progression: Insights From A Multiscale Modeling Study, Joseph D Butner, Prashant Dogra, Caroline Chung, Javier Ruiz-Ramírez, Sara Nizzero, Marija Plodinec, Xiaoxian Li, Ping-Ying Pan, Shu-Hsia Chen, Vittorio Cristini, Bulent Ozpolat, George A Calin, Zhihui Wang

Faculty, Staff and Student Publications

We present a multiscale agent-based model of ductal carcinoma in situ (DCIS) to study how key phenotypic and signaling pathways are involved in the early stages of disease progression. The model includes a phenotypic hierarchy, and key endocrine and paracrine signaling pathways, and simulates cancer ductal growth in a 3D lattice-free domain. In particular, by considering stochastic cell dedifferentiation plasticity, the model allows for study of how dedifferentiation to a more stem-like phenotype plays key roles in the maintenance of cancer stem cell populations and disease progression. Through extensive parameter perturbation studies, we have quantified and ranked how DCIS is …

Development And Characterization Of Anti-Galectin-9 Antibodies That Protect T Cells From Galectin-9-Induced Cell Death, Riyao Yang, Linlin Sun, Ching-Fei Li, Yu-Han Wang, Weiya Xia, Boning Liu, Yu-Yi Chu, Laura Bover, Long Vien, Mien-Chie Hung

Faculty, Staff and Student Publications

Antibodies that target immune checkpoint proteins such as programmed cell death protein 1, programmed death ligand 1, and cytotoxic T-lymphocyte-associated antigen 4 in human cancers have achieved impressive clinical success; however, a significant proportion of patients fail to respond to these treatments. Galectin-9 (Gal-9), a β-galactoside-binding protein, has been shown to induce T-cell death and facilitate immunosuppression in the tumor microenvironment by binding to immunomodulatory receptors such as T-cell immunoglobulin and mucin domain-containing molecule 3 and the innate immune receptor dectin-1, suggesting that it may have potential as a target for cancer immunotherapy. Here, we report the development of two …

Interplay Between Soluble Cd74 And Macrophage-Migration Inhibitory Factor Drives Tumor Growth And Influences Patient Survival In Melanoma, Yasunari Fukuda, Matias A Bustos, Sung-Nam Cho, Jason Roszik, Suyeon Ryu, Victor M Lopez, Jared K Burks, Jeffrey E Lee, Elizabeth A Grimm, Dave S B Hoon, Suhendan Ekmekcioglu

Faculty, Staff and Student Publications

Soluble forms of receptors play distinctive roles in modulating signal-transduction pathways. Soluble CD74 (sCD74) has been identified in sera of inflammatory diseases and implicated in their pathophysiology; however, few relevant data are available in the context of cancer. Here we assessed the composition and production mechanisms, as well as the clinical significance and biological properties, of sCD74 in melanoma. Serum sCD74 levels were significantly elevated in advanced melanoma patients compared with normal healthy donors, and the high ratio of sCD74 to macrophage-migration inhibitory factor (MIF) conferred significant predictive value for prolonged survival in these patients (p = 0.0035). Secretion of …

The Allergy Mediator Histamine Confers Resistance To Immunotherapy In Cancer Patients Via Activation Of The Macrophage Histamine Receptor H1, Hongzhong Li, Yi Xiao, Qin Li, Jun Yao, Xiangliang Yuan, Yuan Zhang, Xuedong Yin, Yohei Saito, Huihui Fan, Ping Li, Wen-Ling Kuo, Angela Halpin, Don L Gibbons, Hideo Yagita, Zhongming Zhao, Da Pang, Guosheng Ren, Cassian Yee, J Jack Lee, Dihua Yu

Faculty, Staff and Student Publications

Reinvigoration of antitumor immunity remains an unmet challenge. Our retrospective analyses revealed that cancer patients who took antihistamines during immunotherapy treatment had significantly improved survival. We uncovered that histamine and histamine receptor H1 (HRH1) are frequently increased in the tumor microenvironment and induce T cell dysfunction. Mechanistically, HRH1-activated macrophages polarize toward an M2-like immunosuppressive phenotype with increased expression of the immune checkpoint VISTA, rendering T cells dysfunctional. HRH1 knockout or antihistamine treatment reverted macrophage immunosuppression, revitalized T cell cytotoxic function, and restored immunotherapy response. Allergy, via the histamine-HRH1 axis, facilitated tumor growth and induced immunotherapy resistance in mice and humans. …

A Transgenic Bacterial Artificial Chromosome Approach To Identify Regulatory Regions That Direct Amhr2 And Osterix Expression In Müllerian Duct Mesenchyme, Malcolm M Moses, Rachel D Mullen, Daniel I Idowu, Peter Maye, Soazik P Jamin, Richard R Behringer

Faculty, Staff and Student Publications

A transgenic mouse approach using bacterial artificial chromosomes (BAC) was used to identify regulatory regions that direct Müllerian duct expression for Amhr2 and Osterix (Osx, also known as Sp7). Amhr2 encodes the receptor that mediates anti-Müllerian hormone (AMH) signaling for Müllerian duct regression in male embryos. Amhr2 is expressed in the Müllerian duct mesenchyme of both male and female embryos. A ∼147-kb BAC clone containing the Amhr2 locus was used to generate transgenic mice. The transgene was able to rescue the block in Müllerian duct regression of Amhr2-null males, suggesting that the BAC clone contains regulatory …

Regulation Of T Cell Function By Protein S-Acylation, Savannah J West, Darren Boehning, Askar M Akimzhanov

Faculty, Staff and Student Publications

S-acylation, the reversible lipidation of free cysteine residues with long-chain fatty acids, is a highly dynamic post-translational protein modification that has recently emerged as an important regulator of the T cell function. The reversible nature of S-acylation sets this modification apart from other forms of protein lipidation and allows it to play a unique role in intracellular signal transduction. In recent years, a significant number of T cell proteins, including receptors, enzymes, ion channels, and adaptor proteins, were identified as S-acylated. It has been shown that S-acylation critically contributes to their function by regulating protein localization, stability and protein-protein interactions. …

The Effects Of Mapk Signaling On The Development Of Cerebellar Granule Cells, Kerry Morgan

Honors Scholar Theses

The granule cells are the most abundant neuronal type in the human brain. Rapid proliferation of granule cell progenitors results in dramatic expansion and folding of the cerebellar cortex during postnatal development. Mis-regulation of this proliferation process causes medulloblastoma, the most prevalent childhood brain tumor. In the developing cerebellum, granule cells are derived from Atoh1-expressing cells, which arise from the upper rhombic lip (the interface between the roof plate and neuroepithelium). In addition to granule cells, the Atoh1 lineage also gives rise to different types of neurons including cerebellar nuclei neurons. In the current study, I have investigated the …

Escherichia Coli Itat Is A Type Ii Toxin That Inhibits Translation By Acetylating Isoleucyl-Trnaile, Brendan Wilcox, Ilya Osterman, Marina Serebryakova, Dmitry Lukyanov, Ekaterina Komarova, Bridget Gollan, Natalia Morozova, Yuri I Wolf, Kira S Makarova, Sophie Helaine, Petr Sergiev, Svetlana Dubiley, Sergei Borukhov, Konstantin Severinov

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Prokaryotic toxin-antitoxin (TA) modules are highly abundant and are involved in stress response and drug tolerance. The most common type II TA modules consist of two interacting proteins. The type II toxins are diverse enzymes targeting various essential intracellular targets. The antitoxin binds to cognate toxin and inhibits its function. Recently, TA modules whose toxins are GNAT-family acetyltransferases were described. For two such systems, the target of acetylation was shown to be aminoacyl-tRNA: the TacT toxin targets aminoacylated elongator tRNAs, while AtaT targets the amino acid moiety of initiating tRNAMet. We show that the itaRT gene pair from Escherichia coli …

Validation Of The Pre-B Cell Receptor As A Therapeutic Target In B Cell Precursor Acute Lymphoblastic Leukemia, Michael Frank Erasmus

Biomedical Sciences ETDs

This dissertation is built upon the fundamental idea that the pre-B cell receptor (pre-BCR) is important to leukemia cell survival and a logical therapeutic target in B cell precursor acute lymphoblastic leukemia (BCP-ALL). The pre-BCR is expressed early at a specific stage during B cell development where it plays a central role in survival of healthy B lymphocytes. This receptor is composed of the membrane heavy chain (mIgμ) associated with surrogate light chain components, 5 and VpreB. Through the use of advanced imaging modalities, in particular two-color single particle tracking (SPT), we showed that pre-BCRs formed transient, homotypic interactions. These …