Cell and Developmental Biology Commons^™

Trimeric Interaction Of Antp-Ubx With Tbp And Homeoprotein Exd In The Genetic Control Of Development In D. Melanogaster, Alely Cecilia Villarreal-Puente, Claudia Dalila Altamirano-Torres, Diana Resendez-Perez

Research Symposium

Homeoproteins specify body segments along the anteroposterior axis during embryo development; they bind DNA through the homeodomain (HD). Homeoproteins bind to similar and repetitive target sequences on DNA, raising the question of how they achieve functional specificity. Homeoproteins form complexes with proteins through the HDs or other regions. Antennapedia (Antp) and Ultrabithorax (Ubx) have an important role in conferring thorax identity; also they are involved in a repression transcriptional mechanism: Ubx binds to Antp promoter repressing its expression. We analyzed if Ubx and Antp perform protein-protein interaction as a regulation mechanism and if the complex Antp-Ubx are involved in trimeric …

Identification Of Tectorigenin As A Natural Pro-Hypoxia Compound: Implications In Modulation Of Cellular Differentiation And Senescence, Mallika Khurana, Renu Wadhwa, Sunil Kaul

Research Symposium

Background: Hypoxia, a suboptimal level of oxygen, evokes stress response in cells and activated hypoxia signaling has been largely established as a pro-metastasis and pro-angiogenic factor for tumor cells. On the other hand, age-related neurodegenerative disorders are characterized by hypoxic environment, accumulation of molecular garbage and induction of premature senescence. Several recent studies have reported anti-stress impact of the intermittent induction of hypoxia signaling in these cells.

Methods: Screening of a phytochemical library using Hypoxia Responsive Element (HRE) driven luciferase as a reporter was carried out to identify hypoxia-modulating phytochemicals. Activation of HIF-1a (master regulator of hypoxia signaling) was validated …

Identification Of The Functional Domain Of The Dense Core Vesicle Biogenesis Factor Hid-1, Blake H. Hummer, Theodore Carter, Breanna L. Sellers, Jenna D. Triplett, Cedric S. Asensio

Biological Sciences: Faculty Scholarship

Large dense core vesicles (LDCVs) mediate the regulated release of neuropeptides and peptide hormones. HID-1 is a trans-Golgi network (TGN) localized peripheral membrane protein contributing to LDCV formation. There is no information about HID-1 structure or domain architecture, and thus it remains unknown how HID-1 binds to the TGN and performs its function. We report that the N-terminus of HID-1 mediates membrane binding through a myristoyl group with a polybasic amino acid patch but lacks specificity for the TGN. In addition, we show that the C-terminus serves as the functional domain. Indeed, this isolated domain, when tethered to the TGN, …

Tmem27 Suppresses Tumor Development By Promoting Ret Ubiquitination, Positioning, And Degradation, Qianjin Guo, Zi-Ming Cheng, Hector Gonzalez-Cantú, Matthew Rotondi, Gabriela Huelgas-Morales, Purushoth Ethiraj, Zhijun Qiu, Jonathan Lefkowitz, Wan Song, Bethany N Landry, Hector Lopez, Cynthia M Estrada-Zuniga, Shivi Goyal, Mohammad Aasif Khan, Timothy J Walker, Exing Wang, Faqian Li, Yanli Ding, Lois M Mulligan, Ricardo C T Aguiar, Patricia L M Dahia

Faculty, Staff and Student Publications

The TMEM127 gene encodes a transmembrane protein of poorly known function that is mutated in pheochromocytomas, neural crest-derived tumors of adrenomedullary cells. Here, we report that, at single-nucleus resolution, TMEM127-mutant tumors share precursor cells and transcription regulatory elements with pheochromocytomas carrying mutations of the tyrosine kinase receptor RET. Additionally, TMEM127-mutant pheochromocytomas, human cells, and mouse knockout models of TMEM127 accumulate RET and increase its signaling. TMEM127 contributes to RET cellular positioning, trafficking, and lysosome-mediated degradation. Mechanistically, TMEM127 binds to RET and recruits the NEDD4 E3 ubiquitin ligase for RET ubiquitination and degradation via TMEM127 C-terminal PxxY motifs. Lastly, increased cell …

Cell-Based Screening Of Antistress Activity Of Some Phytochemicals: Identification, Validation, And Relevance To Old-Age Related Pathologies, Huayue Zhang, Sunil Kaul, Renu Wadhwa

Research Symposium

Background: A variety of environmental stresses have been shown to contribute to poor quality of life, tissue dysfunctions and ailments including metabolic disorders, cognitive impairment, and accelerated aging. Oxidative stress (an imbalance between the production and processing of highly reactive oxygen species) is largely associated with these phenotypes. Whereas drug development and disease therapeutics have advanced remarkably in last three decades, there are still limited options for stress management. Since the later can effectively decrease the disease burden, we aimed to screen phytochemicals with anti-oxidative stress activity using cell-based assays.

Methods: Brain-derived cells were subjected to chemical models of oxidative …

Pro-Apoptosis Activity Of Pogostemon Cablin Benth. Against Nasopharyngeal Carcinoma Through The Bcl-2 Inhibition Signaling Pathway: A Computational Investigation, Aigia Syahraini, Essy Harnelly, Feri Eko Hermanto

Makara Journal of Science

Resistance to chemotherapy and radiotherapy frequently emerges in the later stage of nasopharyngeal carcinoma (NPC) tumorigenesis. The decreased response of NPC to radiotherapy and chemotherapy occurs owing to the inhibition of cancer cell apoptosis by the B-cell lymphoma-2 (BCL-2) protein. Thus, inhibiting BCL-2 protein may become a powerful approach to eliminate NPC through apoptosis regulation. Meanwhile, Pogostemon cablin is reported to exhibit anticancer properties, but there are limited studies on its use for NPC treatment. The objective of this study is to investigate the potential bioactive compounds in P. cablin as anti-apoptosis BCL-2 protein inhibitors using in-silico approach. Natural compounds …

Transgenic Mice Expressing Functional Tcrs Specific To Cardiac Myhc-Α 334–352 On Both Cd4 And Cd8 T Cells Are Resistant To The Development Of Myocarditis On C57bl/6 Genetic Background, Meghna Sur, Mahima T. Rasquinha, Rajkumar Arumugam, Chandirasegaran Massilamany, Arunkumar Gangaplara, Kiruthiga Mone, Ninaad Lasrado, Bharathi Yalaka, Aakash Doiphode, Channabasavaiah Gurumurthy, David J. Steffen, Jay Reddy

School of Veterinary and Biomedical Sciences: Faculty Publications

Myocarditis is a predominant cause of congestive heart failure and sudden death in children and young adolescents that can lead to dilated cardiomyopathy. Lymphocytic myocarditis mediated by T cells can result from the recognition of cardiac antigens that may involve CD4 or CD8 T cells or both. In this report, we describe the generation of T cell receptor (TCR) transgenic mice on a C57BL/6 genetic background specific to cardiac myosin heavy chain (Myhc)-α 334–352 and make the following observations: First, we verified that Myhc-α 334–352 was immunogenic in wild-type C57BL/6 mice and induced antigen-specific CD4 T cell responses despite being …

Effects Of Osmotic Stress On Oxygen Consumption Of Drosophila Cells (Kc167), Ali A. Ahmed, Rajib Hassan, Michael A. Menze

The Cardinal Edge

This article investigates the effect of osmotic stress on a drosophila cell line called Kc167.

The embryonic-derived fly (Drosophila melanogaster) cell line, Kc-167, was employed as a model for water-stress sensitivity in Arthropods. Like mammalian cells, cells derived from the fruit fly contain the same basic set of membranous components found in all eukaryotic cells. A series of experiments were conducted to characterize the mitochondrial repones of Kc167 cells to water stress. Precisely, the oxygen flux in a sealed respirometer chamber containing Kc167 cells was measured under hyperosmotic and control conditions. Mitochondrial uncouplers were used in some experiments for intact …

A Naturally Derived Watercress Flower-Based Phenethyl Isothiocyanate-Enriched Extract Induces The Activation Of Intrinsic Apoptosis Via Subcellular Ultrastructural And Ca2+ Efflux Alterations In An In Vitro Model Of Human Malignant Melanoma, Sotiris Kyriakou, Louiza Potamiti, Nikoletta Demosthenous, Tom Amery, Kyle Stewart, Paul G. Winyard, Rodrigo Franco, Aglaia Pappa, Mihalis I. Panayiotidis

School of Veterinary and Biomedical Sciences: Faculty Publications

The aim of the current study was to (i) extract isolated fractions of watercress flowers enriched in polyphenols, phenethyl isothiocyanate and glucosinolates and (ii) characterize the anticancer mode of action of non-lethal, sub-lethal and lethal concentrations of the most potent extract fraction in primary (A375) and metastatic (COLO-679) melanoma cells as well as non-tumorigenic immortalized keratinocyte (HaCaT) cells. Cytotoxicity was assessed via the Alamar Blue assay, whereas ultrastructural alterations in mitochondria and the endoplasmic reticulum were determined via transmission electron microscopy. Mitochondrial membrane depolarization was determined using Mito-MP dye, whereas apoptosis was evaluated through the activation of caspases-3, -8 and …

Examining Pi3k-Signaling-Dependent Regulation Of Lens Organelle Free Zone Formation Via Immunolocalization And Immunoblotting In Chick Embryos, Rifah Gheyas, A. Sue Menko

Computational Medicine Center Faculty Papers

The elimination of lens organelles during development, required for mature lens function, is an autophagy-dependent mechanism induced through suppression of PI3K signaling. Here, we present a protocol for investigating the signaling pathways responsible for induction of the formation of this lens organelle free zone. We describe steps for preparation of lens organ culture and use of signaling pathway inhibitors. We then detail procedures for analyzing their impact using both confocal microscopy imaging of immunolabeled lens cryosections and immunoblot approaches. For complete details on the use and execution of this protocol, please refer to Gheyas et al. (2022).

The Use Of Prognostic Markers To Predict Disease Progression And Clinical Outcome In Monoclonal Gammopathy Of Undetermined Significance, Smouldering Multiple Myeloma And Multiple Myeloma., Róisín C. Mcmonagle

International Undergraduate Journal of Health Sciences

Multiple Myeloma (MM) is an incurable plasma cell malignancy with a complex and incompletely understood molecular pathogenesis. Monoclonal Gammopathy of Undetermined Significance (MGUS) and Smouldering Multiple Myeloma (SMM) precede MM, with variable risks and rates of disease progression. The continuing high relapse and death rate in MM cases has prompted research into more accurate prognostic markers to predict progression from MGUS and SMM to MM, as well as identify MM cases with aggressive disease, in order to begin early, targeted and effective therapeutic intervention. Many studies have focused on utilising current markers more effectively, including M-protein, serum-free light chain ratio, …

Canine Testes Thin Sections Culture​, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Canine Testes Thin Sections Culture, Nguyen Khoi Nguyen, Ramanpreet Singh

2023 Symposium

Canine testes thin section culture

Testes tissue culture systems would provide a tool to elucidate spermatogenesis mechanisms, with the aim of genetic preservation of mammals, especially endangered species. Our experiment aims to develop a culture system capable of producing viable mammalian sperm cells in vitro.

Dogs were chosen as the model organism because testes are readily available. Canine testes were obtained from a local veterinary clinic. Thin sections were generated using a commercial electric slicer. They then were cleaned using Dulbecco’s Phosphate-Buffered Saline (DPBS) supplemented with antibiotics then cultured in a modified Tissue Culture Medium 199 (TCM-199). Sections were …

Color Stability, Physical Properties And Antifungal Effects Of Zro2 Additions To Experimental Maxillofacial Silicones: Comparisons With Tio2, Mazen Alkahtany, Mark W. Beatty, Fahd Alsalleeh, Thomas M. Petro, Bobby Simetich, You Zhou, Dennis Feely, Grigoris Polyzois

School of Veterinary and Biomedical Sciences: Faculty Publications

(1) Background: Color changes, physical degradation, and fungal infections are challenges to the longevity of maxillofacial polydimethylsiloxane (PDMS) elastomers. This study aimed to evaluate color changes, physical properties, and antifungal properties of PDMS loaded with ZrO₂ and TiO₂ submicron- and nano-sized particles. (2) Methods: A 1% weight of 40 nm or 200 nm diameter ZrO₂ or TiO₂ nanoparticles was mixed into PDMS with 2% functional intrinsic yellow pigment and polymerized. Control materials contained 13% weight 200 nm silica. Samples were exposed to 3000 h of UVB radiation (200 μW/cm²) or darkness. Color parameters L*a*b* …

Appendage Abnormalities In Spiders Induced By An Alternating Temperature Protocol In The Context Of Recent Advances In Molecular Spider Embryology, Teresa Napiorkowska, Julita Templin, Pawel Napiorkowski, Mark A. Townley

Faculty Publications

In the literature there are numerous reports of developmental deformities in arthropods collected in their natural habitat. Since such teratogenically affected individuals are found purely by chance, the causes of their defects are unknown. Numerous potential physical, mechanical, chemical, and biological teratogens have been considered and tested in the laboratory. Thermal shocks, frequently used in teratological research on the spider Eratigena atrica, have led to deformities on both the prosoma and the opisthosoma. In the 2020/2021 breeding season, by applying alternating temperatures (14 °C and 32 °C, changed every 12 h) for the first 10 days of embryonic development, …

Oligodendrocyte 2phatal Reveals Dynamics Of Myelin Degeneration And Repair, Timothy W. Chapman

Dartmouth College Ph.D Dissertations

Oligodendrocytes are responsible for producing myelin in the central nervous system. This lipid-rich coating along axons helps to increase action potential velocity, provide metabolic support to axons, and facilitate fine-tuning of neuronal circuitry. Demyelination and/or myelin dysfunction is widespread in neurodegenerative diseases and aging. Despite this, we know very little about how individual oligodendrocytes, or the myelin sheaths they produce, degenerate. Myelin repair, carried out by resident oligodendrocyte precursor cells (OPCs), is known to occur following myelin damage in certain contexts. We sought to investigate the cellular dynamics of oligodendrocyte degeneration and repair by developing a non-inflammatory demyelination model, combining …

Transcriptional Pausing Factor M1bp Regulates Cellular Homeostasis By Suppressing Autophagy And Apoptosis In Drosophila Eye, Anuradha Venkatakrishnan Chimata, Hannah Darnell, Akanksha Raj, Madhuri Kango-Singh

Biology Faculty Publications

During organogenesis cellular homeostasis plays a crucial role in patterning and growth. The role of promoter proximal pausing of RNA polymerase II, which regulates transcription of several developmental genes by GAGA factor or Motif 1 Binding Protein (M1BP), has not been fully understood in cellular homeostasis. Earlier, we reported that M1BP, a functional homolog of ZKSCAN3, regulates wingless (wg) and caspase-dependent cell death (apoptosis) in the Drosophila eye. Further, blocking apoptosis does not fully rescue the M1BP^RNAi phenotype of reduced eye. Therefore, we looked for other possible mechanism(s). In a forward genetic screen, members of the Jun-amino-terminal-(NH2)-Kinase (JNK) pathway …

The Minimal Suf System Is Not Required For Fe–S Cluster Biogenesis In The Methanogenic Archaeon Methanosarcina Acetivorans, Jasleen Saini, Thomas M. Deere, Daniel J. Lessner

Biological Sciences Faculty Publications and Presentations

Iron–sulfur (Fe–S) proteins are essential for the ability of methanogens to carry out methanogenesis and biological nitrogen fixation (diazotrophy). Nonetheless, the factors involved in Fe–S cluster biogenesis in methanogens remain largely unknown. The minimal SUF Fe–S cluster biogenesis system (i.e., SufBC) is postulated to serve as the primary system in methanogens. Here, the role of SufBC in Methanosarcina acetivorans, which contains two sufCB gene clusters, was investigated. The CRISPRi-dCas9 and CRISPR-Cas9 systems were utilized to repress or delete sufC1B1 and sufC2B2, respectively. Neither the dual repression of sufC1B1 and sufC2B2 nor the deletion of both sufC1B1 and sufC2B2 …

Molecular Mechanisms Regulating Prometaphase And Metaphase States For Faithful Chromosome Segregation, Sarah Yvette Valles

Dartmouth College Ph.D Dissertations

Cells progress through different stages of the cell cycle as they ultimately prepare to divide during mitosis. Mitosis relies on many interconnected networks to carry out the coordinated events required for faithful chromosome segregation. When a cell enters mitosis, chromosomes are highly condensed and sister chromatids are held together by cohesion. Kinetochores assemble at the constricted regions on each chromosome. The kinetochore is a large macromolecular structure composed of many proteins that form the binding site for microtubules of the mitotic spindle to attach. These kinetochore-microtubule (k-MT) attachments serve to align chromosomes at the center of the cell and are …

Metabolic Control Of Proliferation And Differentiation In Oligodendrocytes, Sami Sauma

Dissertations, Theses, and Capstone Projects

Oligodendrocytes (OLs) are specialized cells whose membrane extension, called myelin, wraps the axons providing insulation, trophic and metabolic support, and is essential for proper functioning of the central nervous system. Inappropriate myelin formation, damage or dysfunction of oligodendrocytes has been identified in several neurological disorders and often precedes the loss of neuronal cells. OLs derive from proliferating oligodendrocyte progenitor cells (OPCs), which exit from the cell cycle and undergo a series of transcriptional and epigenetic events, including histone post-translational modifications, resulting in morphological and functional changes. Our lab previously identified elevated levels of histone acetylation in proliferating OPCs during the …