Medicine and Health Sciences Commons^™

Noncanonical Sqstm1/P62-Nrf2 Pathway Activation Mediates Proteasome Inhibitor Resistance In Multiple Myeloma Cells Via Redox, Metabolic And Translational Reprogramming., Irene Riz, Teresa S Hawley, Jeffrey W Marsal, Robert G Hawley

Anatomy and Regenerative Biology Faculty Publications

Multiple Myeloma (MM) is a B-cell malignancy characterized by the accumulation of clonal plasma cells in the bone marrow, with drug resistance being a major cause of therapeutic failure. We established a carfilzomib-resistant derivative of the LP-1 MM cell line (LP-1/Cfz) and found that the transcription factor NF-E2 p45-related factor 2 (Nrf2; gene symbol NFE2L2) contributes to carfilzomib resistance. The mechanism of Nrf2 activation involved enhanced translation of Nrf2 as well as its positive regulator, the autophagy receptor sequestosome 1 (SQSTM1)/p62. The eukaryotic translation initiation factor gene EIF4E3 was among the Nrf2 target genes upregulated in LP-1/Cfz cells, suggesting existence …

High-Sensitivity Mass Spectrometry For Probing Gene Translation In Single Embryonic Cells In The Early Frog (Xenopus) Embryo, Camille Lombard-Banek, Sally Ann Moody, Peter Nemes

Anatomy and Regenerative Biology Faculty Publications

Direct measurement of protein expression with single-cell resolution promises to deepen the understanding of basic molecular processes during normal and impaired development. High-resolution mass spectrometry provides detailed coverage of the proteomic composition of large numbers of cells. Here we discuss recent mass spectrometry developments based on single-cell capillary electrophoresis that extend discovery proteomics to sufficient sensitivity to enable the measurement of proteins in single cells. The single-cell mass spectrometry system is used to detect a large number of proteins in single embryonic cells in blastomeres in the 16-cell embryo of the South African clawed frog (Xenopus laevis) that give rise …

Inflammatory Bowel Disease, Colorectal Cancer And Type 2 Diabetes Mellitus: The Links., Abdo Jurjus, Assad Eid, Sahar Al Kattar, Marie Noel Zeenny, Alice Gerges-Geagea, Rosalyn A. Jurjus, +10 Additional Authors

Anatomy and Regenerative Biology Faculty Publications

The co-occurrence of the three disease entities, inflammatory bowel disease (IBD), colorectal cancer (CRC), type 2diabetes mellitus (T2DM) along with inflammation and dismicrobism has been frequently reported. Some authors have even suggested that dysbiosis could be the link through a molecular crosstalk of multiple inflammatory loops including TGFβ, NFKB, TNFα and ROS among others. This review focuses on the inflammatory process along with the role of microbiota in the pathophysiology of the three diseases. The etiology of IBD is multifactorial, and like CRC and T2DM, it is associated with a widespread and sustained GI inflammation and dismicrobism, whereby an array …

Oligodendrocyte Ablation As A Tool To Study Demyelinating Diseases, Ahdeah Pajoohesh-Ganji, Robert H. Miller

Anatomy and Regenerative Biology Faculty Publications

Multiple sclerosis (MS) is an autoimmune mediated neurodegenerative disease characterized by demyelination and oligodendrocyte (OL) loss in the central nervous system and accompanied by local inflammation and infiltration of peripheral immune cells. Although many risk factors and symptoms have been identified in MS, the pathology is complicated and the cause remains unknown. It is also unclear whether OL apoptosis precedes the inflammation or whether the local inflammation is the cause of OL death and demyelination. This review briefly discusses several models that have been developed to specifically ablate oligodendrocytes in an effort to separate the effects of demyelination from inflammation.

Localized Jnk Signaling Regulates Organ Size During Development., Helen Rankin Willsey, Xiaoyan Zheng, José Carlos Pastor-Pareja, A Jeremy Willsey, Philip A Beachy, Tian Xu

Anatomy and Regenerative Biology Faculty Publications

A fundamental question of biology is what determines organ size. Despite demonstrations that factors within organs determine their sizes, intrinsic size control mechanisms remain elusive. Here we show that Drosophila wing size is regulated by JNK signaling during development. JNK is active in a stripe along the center of developing wings, and modulating JNK signaling within this stripe changes organ size. This JNK stripe influences proliferation in a non-canonical, Jun-independent manner by inhibiting the Hippo pathway. Localized JNK activity is established by Hedgehog signaling, where Ci elevates dTRAF1 expression. As the dTRAF1 homolog, TRAF4, is amplified in numerous cancers, these …

K14+ Compound Niches Are Present On The Mouse Cornea Early After Birth And Expand After Debridement Wounds., Ahdeah Pajoohesh-Ganji, Sonali Pal-Ghosh, Gauri Tadvalkar, Mary Ann Stepp

Anatomy and Regenerative Biology Faculty Publications

Background: We previously identified compound niches (CNs) at the limbal:corneal border of the mouse cornea that contain corneal epithelial progenitor cells, express Keratin 8 (K8), and goblet cell mucin Muc5AC. During re-epithelialization after 2.5 mm epithelial debridement wounds, CNs migrate onto the cornea and expand in number mimicking conjunctivalization. When CNs form during development and whether they express corneal epithelial progenitor cell enriched K14 was not known.

Results: To provide insight into corneal epithelial homeostasis, we quantify changes in expression of simple (K8, K18, K19) and stratified squamous epithelial keratins (K5, K12, K14, and K15) during postnatal development and in …

Single-Cell Mass Spectrometry For Discovery Proteomics: Quantifying Translational Cell Heterogeneity In The 16-Cell Frog (Xenopus) Embryo, Camille Lombard-Banek, Sally Ann Moody, Peter Nemes

Anatomy and Regenerative Biology Faculty Publications

We advance mass spectrometry from a cell population-averaging tool to one capable of quantifying the expression of diverse proteins in single embryonic cells. Our instrument combines capillary electrophoresis (CE), electrospray ionization, and a tribrid ultrahigh-resolution mass spectrometer (HRMS) to enable untargeted (discovery) proteomics with ca. 25 amol lower limit of detection. CE-μESI-HRMS enabled the identification of 500–800 nonredundant protein groups by measuring 20 ng, or <0.2% of the total protein content in single blastomeres that were isolated from the 16-cell frog (Xenopus laevis) embryo, amounting to a total of 1709 protein groups identified between n=3 biological replicates. By quantifying ≈150 nonredundant protein groups between all blastomeres and replicate measurements, we found significant translational cell heterogeneity along multiple axes of the embryo at this very early stage of development when the transcriptional program of the embryo has yet to begin.