Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 9 of 9
Full-Text Articles in Medicine and Health Sciences
Neuromuscular Junction Pathology Is Correlated With Differential Motor Unit Vulnerability In Spinal And Bulbar Muscular Atrophy, Elana Molotsky, Y Liu, Andrew P Lieberman, Diane E Merry
Neuromuscular Junction Pathology Is Correlated With Differential Motor Unit Vulnerability In Spinal And Bulbar Muscular Atrophy, Elana Molotsky, Y Liu, Andrew P Lieberman, Diane E Merry
Department of Biochemistry and Molecular Biology Faculty Papers
Spinal and bulbar muscular atrophy (SBMA) is an X-linked, neuromuscular neurodegenerative disease for which there is no cure. The disease is characterized by a selective decrease in fast-muscle power (e.g., tongue pressure, grip strength) accompanied by a selective loss of fast-twitch muscle fibers. However, the relationship between neuromuscular junction (NMJ) pathology and fast-twitch motor unit vulnerability has yet to be explored. In this study, we used a cross-model comparison of two mouse models of SBMA to evaluate neuromuscular junction pathology, glycolytic-to-oxidative fiber-type switching, and cytoskeletal alterations in pre- and postsynaptic termini of tibialis anterior (TA), gastrocnemius, and soleus hindlimb muscles. …
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
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 …
Chloride Sensing By Wnk1 Regulates Nlrp3 Inflammasome Activation And Pyroptosis., Lindsey Mayes-Hopfinger, Aura Enache, Jian Xie, Chou-Long Huang, Robert Köchl, Victor L.J. Tybulewicz, Teresa Fernandes-Alnemri, Emad S. Alnemri
Chloride Sensing By Wnk1 Regulates Nlrp3 Inflammasome Activation And Pyroptosis., Lindsey Mayes-Hopfinger, Aura Enache, Jian Xie, Chou-Long Huang, Robert Köchl, Victor L.J. Tybulewicz, Teresa Fernandes-Alnemri, Emad S. Alnemri
Department of Biochemistry and Molecular Biology Faculty Papers
The NLRP3 inflammasome mediates the production of proinflammatory cytokines and initiates inflammatory cell death. Although NLRP3 is essential for innate immunity, aberrant NLRP3 inflammasome activation contributes to a wide variety of inflammatory diseases. Understanding the pathways that control NLRP3 activation will help develop strategies to treat these diseases. Here we identify WNK1 as a negative regulator of the NLRP3 inflammasome. Macrophages deficient in WNK1 protein or kinase activity have increased NLRP3 activation and pyroptosis compared with control macrophages. Mice with conditional knockout of WNK1 in macrophages have increased IL-1β production in response to NLRP3 stimulation compared with control mice. Mechanistically, …
Gasdermin Pores Permeabilize Mitochondria To Augment Caspase-3 Activation During Apoptosis And Inflammasome Activation., Corey Rogers, Dan A. Erkes, Alexandria Nardone, Andrew E. Aplin, Teresa Fernandes-Alnemri, Emad S. Alnemri
Gasdermin Pores Permeabilize Mitochondria To Augment Caspase-3 Activation During Apoptosis And Inflammasome Activation., Corey Rogers, Dan A. Erkes, Alexandria Nardone, Andrew E. Aplin, Teresa Fernandes-Alnemri, Emad S. Alnemri
Department of Biochemistry and Molecular Biology Faculty Papers
Gasdermin E (GSDME/DFNA5) cleavage by caspase-3 liberates the GSDME-N domain, which mediates pyroptosis by forming pores in the plasma membrane. Here we show that GSDME-N also permeabilizes the mitochondrial membrane, releasing cytochrome c and activating the apoptosome. Cytochrome c release and caspase-3 activation in response to intrinsic and extrinsic apoptotic stimuli are significantly reduced in GSDME-deficient cells comparing with wild type cells. GSDME deficiency also accelerates cell growth in culture and in a mouse model of melanoma. Phosphomimetic mutation of the highly conserved phosphorylatable Thr6 residue of GSDME, inhibits its pore-forming activity, thus uncovering a potential mechanism by which GSDME …
Disrupting Sumoylation Enhances Transcriptional Function And Ameliorates Polyglutamine Androgen Receptor-Mediated Disease., Jason P Chua, Satya L Reddy, Zhigang Yu, Elisa Giorgetti, Heather L Montie, Sarmistha Mukherjee, Jake Higgins, Richard C Mceachin, Diane M Robins, Diane E Merry, Jorge A Iñiguez-Lluhí, Andrew P Lieberman
Disrupting Sumoylation Enhances Transcriptional Function And Ameliorates Polyglutamine Androgen Receptor-Mediated Disease., Jason P Chua, Satya L Reddy, Zhigang Yu, Elisa Giorgetti, Heather L Montie, Sarmistha Mukherjee, Jake Higgins, Richard C Mceachin, Diane M Robins, Diane E Merry, Jorge A Iñiguez-Lluhí, Andrew P Lieberman
Department of Biochemistry and Molecular Biology Faculty Papers
Expansion of the polyglutamine (polyQ) tract within the androgen receptor (AR) causes neuromuscular degeneration in individuals with spinobulbar muscular atrophy (SBMA). PolyQ AR has diminished transcriptional function and exhibits ligand-dependent proteotoxicity, features that have both been implicated in SBMA; however, the extent to which altered AR transcriptional function contributes to pathogenesis remains controversial. Here, we sought to dissociate effects of diminished AR function from polyQ-mediated proteotoxicity by enhancing the transcriptional activity of polyQ AR. To accomplish this, we bypassed the inhibitory effect of AR SUMOylation (where SUMO indicates small ubiquitin-like modifier) by mutating conserved lysines in the polyQ AR that …
Global Cellular Regulation Including Cardiac Function By Post-Translational Protein Arginylation., Hideko Kaji, Akira Kaji
Global Cellular Regulation Including Cardiac Function By Post-Translational Protein Arginylation., Hideko Kaji, Akira Kaji
Department of Biochemistry and Molecular Biology Faculty Papers
In this issue a very significant contribution to cardiology describing critical roles of ATE1 appears by Kurosaka et al. [1]. In view of this paper, as the discoverers of ATE1, we have been asked to contribute an article (editorial) regarding ATE1 (enzyme which transfers arginine from arginyl tRNA to protein acceptors). This short article consists of three sections: 1) a historical anecdote describing how ATE1 was discovered; 2) its possible role in aging and cellular transformation, and most importantly; 3) its role in the development and maintenance of cardiac activity. The last section has direct bearing to the Kurosaka …
Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry
Testosterone Treatment Fails To Accelerate Disease In A Transgenic Mouse Model Of Spinal And Bulbar Muscular Atrophy., Erica S Chevalier-Larsen, Diane E Merry
Department of Biochemistry and Molecular Biology Faculty Papers
Evidence from multiple animal models demonstrates that testosterone plays a crucial role in the progression of symptoms in spinal and bulbar muscular atrophy (SBMA), a condition that results in neurodegeneration and muscle atrophy in affected men. Mice bearing a transgene encoding a human androgen receptor (AR) that contains a stretch of 112 glutamines (expanded polyglutamine tract; AR112Q mice) reproduce several aspects of the human disease. We treated transgenic male AR112Q mice with testosterone for 6 months. Surprisingly, testosterone treatment of AR112Q males did not exacerbate the disease. Although transgenic AR112Q males exhibited functional deficits when compared with non-transgenics, long-term testosterone …
Rad51c Deficiency In Mice Results In Early Prophase I Arrest In Males And Sister Chromatid Separation At Metaphase Ii In Females, Sergey Kuznetsov, Manuela Pellegrini, Kristy Shuda, Oscar Fernandez-Capetillo, Yilun Liu, Betty K. Martin, Sandra Burkett, Eileen Southon, Debananda Pati, Lino Tessarollo, Stephen D. West, Peter J. Donovan, Andre Nussenzweig, Shyam K. Sharan
Rad51c Deficiency In Mice Results In Early Prophase I Arrest In Males And Sister Chromatid Separation At Metaphase Ii In Females, Sergey Kuznetsov, Manuela Pellegrini, Kristy Shuda, Oscar Fernandez-Capetillo, Yilun Liu, Betty K. Martin, Sandra Burkett, Eileen Southon, Debananda Pati, Lino Tessarollo, Stephen D. West, Peter J. Donovan, Andre Nussenzweig, Shyam K. Sharan
Department of Biochemistry and Molecular Biology Faculty Papers
RAD51C is a member of the RecA/RAD51 protein family, which is known to play an important role in DNA repair by homologous recombination. In mice, it is essential for viability. Therefore, we have generated a hypomorphic allele of Rad51c in addition to a null allele. A subset of mice expressing the hypomorphic allele is infertile. This infertility is caused by sexually dimorphic defects in meiotic recombination, revealing its two distinct functions. Spermatocytes undergo a developmental arrest during the early stages of meiotic prophase I, providing evidence for the role of RAD51C in early stages of RAD51-mediated recombination. In contrast, oocytes …
Murine Transporter Associated With Antigen Presentation (Tap) Preferences Influence Class I-Restricted T Cell Responses., A J Yellen-Shaw, C E Laughlin, R M Metrione, Laurence C. Eisenlohr
Murine Transporter Associated With Antigen Presentation (Tap) Preferences Influence Class I-Restricted T Cell Responses., A J Yellen-Shaw, C E Laughlin, R M Metrione, Laurence C. Eisenlohr
Department of Biochemistry and Molecular Biology Faculty Papers
The transporter associated with antigen presentation (TAP) complex shuttles cytosolic peptides into the exocytic compartment for association with nascent major histocompatibility complex class I molecules. Biochemical studies of murine and human TAP have established that substrate length and COOH-terminal residue identity are strong determinants of transport efficiency. However, the existence of these specificities in the intact cell and their influences on T cell responses have not been demonstrated. We have devised a method for studying TAP- mediated transport in intact cells, using T cell activation as a readout. The approach makes use of a panel of recombinant vaccinia viruses expressing …