1
|
Roland BP, Zeccola AM, Larsen SB, Amrich CG, Talsma AD, Stuchul KA, Heroux A, Levitan ES, VanDemark AP, Palladino MJ. Structural and Genetic Studies Demonstrate Neurologic Dysfunction in Triosephosphate Isomerase Deficiency Is Associated with Impaired Synaptic Vesicle Dynamics. PLoS Genet 2016; 12:e1005941. [PMID: 27031109 PMCID: PMC4816394 DOI: 10.1371/journal.pgen.1005941] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 02/24/2016] [Indexed: 01/05/2023] Open
Abstract
Triosephosphate isomerase (TPI) deficiency is a poorly understood disease characterized by hemolytic anemia, cardiomyopathy, neurologic dysfunction, and early death. TPI deficiency is one of a group of diseases known as glycolytic enzymopathies, but is unique for its severe patient neuropathology and early mortality. The disease is caused by missense mutations and dysfunction in the glycolytic enzyme, TPI. Previous studies have detailed structural and catalytic changes elicited by disease-associated TPI substitutions, and samples of patient erythrocytes have yielded insight into patient hemolytic anemia; however, the neuropathophysiology of this disease remains a mystery. This study combines structural, biochemical, and genetic approaches to demonstrate that perturbations of the TPI dimer interface are sufficient to elicit TPI deficiency neuropathogenesis. The present study demonstrates that neurologic dysfunction resulting from TPI deficiency is characterized by synaptic vesicle dysfunction, and can be attenuated with catalytically inactive TPI. Collectively, our findings are the first to identify, to our knowledge, a functional synaptic defect in TPI deficiency derived from molecular changes in the TPI dimer interface.
Collapse
Affiliation(s)
- Bartholomew P. Roland
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Alison M. Zeccola
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Samantha B. Larsen
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Christopher G. Amrich
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Aaron D. Talsma
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Kimberly A. Stuchul
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Annie Heroux
- Energy Sciences Directorate/Photon Science Division, Brookhaven National Laboratory, Upton, New York, United States of America
| | - Edwin S. Levitan
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Andrew P. VanDemark
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Michael J. Palladino
- Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- The Pittsburgh Institute for Neurodegenerative Diseases (PIND), University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
- * E-mail:
| |
Collapse
|
2
|
Singh S, Plaks JG, Homa NJ, Amrich CG, Héroux A, Hatfull GF, VanDemark AP. The structure of Xis reveals the basis for filament formation and insight into DNA bending within a mycobacteriophage intasome. J Mol Biol 2013; 426:412-22. [PMID: 24112940 DOI: 10.1016/j.jmb.2013.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Revised: 09/26/2013] [Accepted: 10/01/2013] [Indexed: 11/27/2022]
Abstract
The recombination directionality factor, Xis, is a DNA bending protein that determines the outcome of integrase-mediated site-specific recombination by redesign of higher-order protein-DNA architectures. Although the attachment site DNA of mycobacteriophage Pukovnik is likely to contain four sites for Xis binding, Xis crystals contain five subunits in the asymmetric unit, four of which align into a Xis filament and a fifth that is generated by an unusual domain swap. Extensive intersubunit contacts stabilize a bent filament-like arrangement with Xis monomers aligned head to tail. The structure implies a DNA bend of ~120°, which is in agreement with DNA bending measured in vitro. Formation of attR-containing intasomes requires only Int and Xis, distinguishing Pukovnik from lambda. Therefore, we conclude that, in Pukovnik, Xis-induced DNA bending is sufficient to promote intramolecular Int-mediated bridges during intasome formation.
Collapse
Affiliation(s)
- Shweta Singh
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Joseph G Plaks
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Nicholas J Homa
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA; Present address: N. J. Homa, 426 CARL Building, Duke University, Durham, NC 27710, USA.
| | - Christopher G Amrich
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Annie Héroux
- Department of Biology, Brookhaven National Laboratory, Upton, NY 11973, USA
| | - Graham F Hatfull
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Andrew P VanDemark
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| |
Collapse
|
3
|
Roland BP, Stuchul KA, Larsen SB, Amrich CG, Vandemark AP, Celotto AM, Palladino MJ. Evidence of a triosephosphate isomerase non-catalytic function crucial to behavior and longevity. J Cell Sci 2013; 126:3151-8. [PMID: 23641070 DOI: 10.1242/jcs.124586] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Triosephosphate isomerase (TPI) is a glycolytic enzyme that converts dihydroxyacetone phosphate (DHAP) into glyceraldehyde 3-phosphate (GAP). Glycolytic enzyme dysfunction leads to metabolic diseases collectively known as glycolytic enzymopathies. Of these enzymopathies, TPI deficiency is unique in the severity of neurological symptoms. The Drosophila sugarkill mutant closely models TPI deficiency and encodes a protein prematurely degraded by the proteasome. This led us to question whether enzyme catalytic activity was crucial to the pathogenesis of TPI sugarkill neurological phenotypes. To study TPI deficiency in vivo we developed a genomic engineering system for the TPI locus that enables the efficient generation of novel TPI genetic variants. Using this system we demonstrate that TPI sugarkill can be genetically complemented by TPI encoding a catalytically inactive enzyme. Furthermore, our results demonstrate a non-metabolic function for TPI, the loss of which contributes significantly to the neurological dysfunction in this animal model.
Collapse
Affiliation(s)
- Bartholomew P Roland
- Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261, USA
| | | | | | | | | | | | | |
Collapse
|
4
|
Amrich CG, Davis CP, Rogal WP, Shirra MK, Heroux A, Gardner RG, Arndt KM, VanDemark AP. Cdc73 subunit of Paf1 complex contains C-terminal Ras-like domain that promotes association of Paf1 complex with chromatin. J Biol Chem 2012; 287:10863-75. [PMID: 22318720 DOI: 10.1074/jbc.m111.325647] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The conserved Paf1 complex localizes to the coding regions of genes and facilitates multiple processes during transcription elongation, including the regulation of histone modifications. However, the mechanisms that govern Paf1 complex recruitment to active genes are undefined. Here we describe a previously unrecognized domain within the Cdc73 subunit of the Paf1 complex, the Cdc73 C-domain, and demonstrate its importance for Paf1 complex occupancy on transcribed chromatin. Deletion of the C-domain causes phenotypes associated with elongation defects without an apparent loss of complex integrity. Simultaneous mutation of the C-domain and another subunit of the Paf1 complex, Rtf1, causes enhanced mutant phenotypes and loss of histone H3 lysine 36 trimethylation. The crystal structure of the C-domain reveals unexpected similarity to the Ras family of small GTPases. Instead of a deep nucleotide-binding pocket, the C-domain contains a large but comparatively flat surface of highly conserved residues, devoid of ligand. Deletion of the C-domain results in reduced chromatin association for multiple Paf1 complex subunits. We conclude that the Cdc73 C-domain probably constitutes a protein interaction surface that functions with Rtf1 in coupling the Paf1 complex to the RNA polymerase II elongation machinery.
Collapse
Affiliation(s)
- Christopher G Amrich
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA
| | | | | | | | | | | | | | | |
Collapse
|