Cell Biology Commons^™

Nucleus Accumbens Core Single Cell Ensembles Bidirectionally Respond To Experienced Versus Observed Aversive Events, Oyku Dinckol, Noah Harris Wenger, Jennifer E Zachry, Munir Gunes Kutlu

Rowan-Virtua School of Osteopathic Medicine Faculty Scholarship

Fear learning is a critical feature of survival skills among mammals. In rodents, fear learning manifests itself through direct experience of the aversive event or social transmission of aversive stimuli such as observing and acting on conspecifics' distress. The neuronal network underlying the social transmission of information largely overlaps with the brain regions that mediate behavioral responses to aversive and rewarding stimuli. In this study, we recorded single cell activity patterns of nucleus accumbens (NAc) core neurons using in vivo optical imaging of calcium transients via miniature scopes. This cutting-edge imaging methodology not only allows us to record activity patterns …

Immunological And Hematological Outcomes Following Protracted Low Dose/Low Dose Rate Ionizing Radiation And Simulated Microgravity, Amber M. Paul, Eliah G. Overbey, Willian A. Da Silveira, Nathaniel Szewczyk, Nina C. Nishiyama, Michael J. Pecaut, Sulekha Anand, Jonathan M. Galazka, Xiao Wen Mao

Publications

Using a ground-based model to simulate spaceflight [21-days of single-housed, hindlimb unloading (HLU) combined with continuous low-dose gamma irradiation (LDR, total dose of 0.04 Gy)], an in-depth survey of the immune and hematological systems of mice at 7-days post-exposure was performed. Collected blood was profiled with a hematology analyzer and spleens were analyzed by whole transcriptome shotgun sequencing (RNA-sequencing). The results revealed negligible differences in immune differentials. However, hematological system analyses of whole blood indicated large disparities in red blood cell differentials and morphology, suggestive of anemia. Murine Reactome networks indicated majority of spleen cells displayed differentially expressed genes (DEG) …

A Naturally Generated Decoy Of The Prostate Apoptosis Response-4 Protein Overcomes Therapy Resistance In Tumors, Nikhil Hebbar, Ravshan Burikhanov, Nidhi Shukla, Shirley Qiu, Yanming Zhao, Kojo S. J. Elenitoba-Johnson, Vivek M. Rangnekar

Radiation Medicine Faculty Publications

Primary tumors are often heterogeneous, composed of therapy-sensitive and emerging therapy-resistant cancer cells. Interestingly, treatment of therapy-sensitive tumors in heterogeneous tumor microenvironments results in apoptosis of therapy-resistant tumors. In this study, we identify a prostate apoptosis response-4 (Par-4) amino-terminal fragment (PAF) that is released by diverse therapy-sensitive cancer cells following therapy-induced caspase cleavage of the tumor suppressor Par-4 protein. PAF caused apoptosis in cancer cells resistant to therapy and inhibited tumor growth. A VASA segment of Par-4 mediated its binding and degradation by the ubiquitin ligase Fbxo45, resulting in loss of Par-4 proapoptotic function. Conversely, PAF, which contains this VASA …

Relb Expression Determines The Differential Effects Of Ascorbic Acid In Normal And Cancer Cells, Xiaowei Wei, Yong Xu, Fang Fang Xu, Luksana Chaiswing, David M. Schnell, Teresa Noel, Chi Wang, Jinfei Chen, Daret K. St. Clair, William H. St. Clair

Toxicology and Cancer Biology Faculty Publications

Cancer cells typically experience higher oxidative stress than normal cells, such that elevating pro-oxidant levels can trigger cancer cell death. Although pre-exposure to mild oxidative agents will sensitize cancer cells to radiation, this pre-exposure may also activate the adaptive stress defense system in normal cells. Ascorbic acid is a prototype redox modulator that when infused intravenously appears to kill cancers without injury to normal tissues; however, the mechanisms involved remain elusive. In this study, we show how ascorbic acid kills cancer cells and sensitizes prostate cancer to radiation therapy while also conferring protection upon normal prostate epithelial cells against radiation-induced …

Pleckstrin Homology (Ph) Domain Leucine-Rich Repeat Protein Phosphatase Controls Cell Polarity By Negatively Regulating The Activity Of Atypical Protein Kinase C, Xiaopeng Xiong, Xin Li, Yang-An Wen, Tianyan Gao

Markey Cancer Center Faculty Publications

The proper establishment of epithelial polarity allows cells to sense and respond to signals that arise from the microenvironment in a spatiotemporally controlled manner. Atypical PKCs (aPKCs) are implicated as key regulators of epithelial polarity. However, the molecular mechanism underlying the negative regulation of aPKCs remains largely unknown. In this study, we demonstrated that PH domain leucine-rich repeat protein phosphatase (PHLPP), a novel family of Ser/Thr protein phosphatases, plays an important role in regulating epithelial polarity by controlling the phosphorylation of both aPKC isoforms. Altered expression of PHLPP1 or PHLPP2 disrupted polarization of Caco2 cells grown in 3D cell cultures …

Expression And Function Of Pannexins In The Inner Ear And Hearing, Hong-Bo Zhao

Otolaryngology--Head & Neck Surgery Faculty Publications

Pannexin (Panx) is a gene family encoding gap junction proteins in vertebrates. So far, three isoforms (Panx1, 2 and 3) have been identified. All of three Panx isoforms express in the cochlea with distinct expression patterns. Panx1 expresses in the cochlea extensively, including the spiral limbus, the organ of Corti, and the cochlear lateral wall, whereas Panx2 and Panx3 restrict to the basal cells of the stria vascularis in the lateral wall and the cochlear bony structure, respectively. However, there is no pannexin expression in auditory sensory hair cells. Recent studies demonstrated that like connexin gap junction gene, Panx1 deficiency …

P-Rex1 Promotes Resistance To Vegf/Vegfr-Targeted Therapy In Prostate Cancer, Hira Lal Goel, Bryan Pursell, Leonard D. Shultz, Dale L. Greiner, Rolf A Brekken, Craig W. Vander Kooi, Arthur M. Mercurio

Molecular and Cellular Biochemistry Faculty Publications

Autocrine VEGF signaling is critical for sustaining prostate and other cancer stem cells (CSCs), and it is a potential therapeutic target, but we observed that CSCs isolated from prostate tumors are resistant to anti-VEGF (bevacizumab) and anti-VEGFR (sunitinib) therapy. Intriguingly, resistance is mediated by VEGF/neuropilin signaling, which is not inhibited by bevacizumab and sunitinib, and it involves the induction of P-Rex1, a Rac GEF, and consequent Rac1-mediated ERK activation. This induction of P-Rex1 is dependent on Myc. CSCs isolated from the PTEN^pc−/− transgenic model of prostate cancer exhibit Rac1-dependent resistance to bevacizumab. Rac1 inhibition or P-Rex1 downregulation increases the …

A Mutation In The Mouse Chd2 Chromatin Remodeling Enzyme Results In A Complex Renal Phenotype, Concetta Marfella, Nils Henninger, Scott Leblanc, Namrata Krishnan, David Garlick, Lawrence Holzman, Anthony Imbalzano

Nils Henninger

BACKGROUND AND AIMS: Glomerular diseases are the third leading cause of kidney failure worldwide, behind only diabetes and hypertension. The molecular mechanisms underlying the cause of glomerular diseases are still largely unknown. The identification and characterization of new molecules associated with glomerular function should provide new insights into understanding the diverse group of glomerular diseases. The Chd2 protein belongs to a family of enzymes involved in ATP-dependent chromatin remodeling, suggesting that it likely functions as an epigenetic regulator of gene expression via the modification of chromatin structure. METHODS: In this study, we present a detailed histomorphologic characterization of mice containing …

Sting-Irf3 Pathway Links Endoplasmic Reticulum Stress With Hepatocyte Apoptosis In Early Alcoholic Liver Disease, Jan Petrasek, Arvin Iracheta-Vellve, Timea Csak, Abhishek Satishchandran, Karen Kodys, Evelyn A. Kurt-Jones, Katherine A. Fitzgerald, Gyongyi Szabo

Katherine A. Fitzgerald

Emerging evidence suggests that innate immunity drives alcoholic liver disease (ALD) and that the interferon regulatory factor 3 (IRF3),a transcription factor regulating innate immune responses, is indispensable for the development of ALD. Here we report that IRF3 mediates ALD via linking endoplasmic reticulum (ER) stress with apoptotic signaling in hepatocytes. We found that ethanol induced ER stress and triggered the association of IRF3 with the ER adaptor, stimulator of interferon genes (STING), as well as subsequent phosphorylation of IRF3. Activated IRF3 associated with the proapoptotic molecule Bax [B-cell lymphoma 2 (Bcl2)-associated X protein] and contributed to hepatocyte apoptosis. Deficiency of …

Sting-Irf3 Pathway Links Endoplasmic Reticulum Stress With Hepatocyte Apoptosis In Early Alcoholic Liver Disease, Jan Petrasek, Arvin Iracheta-Vellve, Timea Csak, Abhishek Satishchandran, Karen Kodys, Evelyn A. Kurt-Jones, Katherine A. Fitzgerald, Gyongyi Szabo

Gyongyi Szabo

Emerging evidence suggests that innate immunity drives alcoholic liver disease (ALD) and that the interferon regulatory factor 3 (IRF3),a transcription factor regulating innate immune responses, is indispensable for the development of ALD. Here we report that IRF3 mediates ALD via linking endoplasmic reticulum (ER) stress with apoptotic signaling in hepatocytes. We found that ethanol induced ER stress and triggered the association of IRF3 with the ER adaptor, stimulator of interferon genes (STING), as well as subsequent phosphorylation of IRF3. Activated IRF3 associated with the proapoptotic molecule Bax [B-cell lymphoma 2 (Bcl2)-associated X protein] and contributed to hepatocyte apoptosis. Deficiency of …

Bcma Is Essential For The Survival Of Long-Lived Bone Marrow Plasma Cells, Brian P. O'Connor, Vanitha S. Raman, Loren D. Erickson, W. James Cook, Lehn K. Weaver, Cory Ahonen, Ling-Li Lin, George Mantchev, Richard J. Bram, Randolph J. Noelle

Dartmouth Scholarship

Long-lived humoral immunity is manifested by the ability of bone marrow plasma cells (PCs) to survive for extended periods of time. Recent studies have underscored the importance of BLyS and APRIL as factors that can support the survival of B lineage lymphocytes. We show that BLyS can sustain PC survival in vitro, and this survival can be further enhanced by inter- leukin 6. Selective up-regulation of Mcl-1 in PCs by BLyS suggests that this 􏰀-apoptotic gene product may play an important role in PC survival. Blockade of BLyS, via transmembrane activator and cyclophilin ligand interactor–immunoglobulin treatment, inhibited PC survival in …

Insulinlike Growth Factor 1- And 2-Augmented Collagen Gel Repair Of Facial Osseous Defects, James S. Toung, Roy C. Ogle, Raymond F. Morgan, William H. Lindsey

Medical Diagnostics & Translational Sciences Faculty Publications

BACKGROUND: Defects of the facial bone structure are common problems for the facial plastic surgeon. Native type 1 collagen gels (T1CGs) have been shown to mediate repair of facial critical-size defects in rat models.

OBJECTIVE: To evaluate the efficacy of T1CG augmented with insulinlike growth factor (IGF) 1, IGF-2, and a combination of IGF-1 and IGF-2 on the repair of facial critical-size defects in a rodent model.

METHODS: Twenty-four retired male breeder Sprague-Dawley rats were divided into 4 groups of 6 animals. Facial critical-size defects were created by removing the nasalis bones with a bone-cutting drill. Defects were treated with …