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- Keyword
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- Aquaporins (2)
- Calmodulin (2)
- Electron microscopy (2)
- Protein kinases (2)
- Calcium -- Regulation (1)
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- Cataract -- Molecular aspects (1)
- Cellular control mechanisms (1)
- Cryomicroscopy (1)
- Crystallography (1)
- Leucine -- Metabolism (1)
- Lipids -- Microstructure (1)
- Membrane proteins (1)
- Membrane proteins -- Structure (1)
- Mitochondria (1)
- Molecular dynamics (1)
- Phosphorylation (1)
- Protein folding (1)
- Proteins -- Conformation (1)
- Structural dynamics (1)
- Transfer RNA -- Structure (1)
Articles 1 - 5 of 5
Full-Text Articles in Biochemistry
Structural Dynamics Of A Mitochondrial Trna Possessing Weak Thermodynamic Stability, Hari Bhaskaran, Takaaki Taniguchi, Takeo Suzuki, Tsutomu Suzuki, John J. Perona
Structural Dynamics Of A Mitochondrial Trna Possessing Weak Thermodynamic Stability, Hari Bhaskaran, Takaaki Taniguchi, Takeo Suzuki, Tsutomu Suzuki, John J. Perona
Chemistry Faculty Publications and Presentations
Folding dynamics are ubiquitously involved in controlling the multivariate functions of RNAs. While the high thermodynamic stabilities of some RNAs favor purely native states at equilibrium, it is unclear whether weakly stable RNAs exist in random, partially folded states or sample well-defined, globally folded conformations. Using a folding assay that precisely tracks the formation of native aminoacylable tRNA, we show that the folding of a weakly stable human mitochondrial (hmt) leucine tRNA is hierarchical with a distinct kinetic folding intermediate. The stabilities of the native and intermediate conformers are separated by only about 1.2 kcal/mol, and the species are readily …
Intrinsic Disorder Within An Akap-Protein Kinase A Complex Guides Local Substrate Phosphorylation, F. Donelson Smith, Steve L. Reichow, Jessica L. Esseltine, Dan Shi, Lorene K. Langeberg, John D. Scott, Tamir Gonen
Intrinsic Disorder Within An Akap-Protein Kinase A Complex Guides Local Substrate Phosphorylation, F. Donelson Smith, Steve L. Reichow, Jessica L. Esseltine, Dan Shi, Lorene K. Langeberg, John D. Scott, Tamir Gonen
Chemistry Faculty Publications and Presentations
Anchoring proteins sequester kinases with their substrates to locally disseminate intracellular signals and avert indiscriminate transmission of these responses throughout the cell. Mechanistic understanding of this process is hampered by limited structural information on these macromolecular complexes. A-kinase anchoring proteins (AKAPs) spatially constrain phosphorylation by cAMP-dependent protein kinases (PKA). Electron microscopy and three-dimensional reconstructions of type-II PKA-AKAP18γ complexes reveal hetero-pentameric assemblies that adopt a range of flexible tripartite configurations. Intrinsically disordered regions within each PKA regulatory subunit impart the molecular plasticity that affords an ∼16 nanometer radius of motion to the associated catalytic subunits. Manipulating flexibility within the PKA holoenzyme …
Allosteric Mechanism Of Water Channel Gating By Ca2+–Calmodulin, Steve Reichow, Daniel M. Clemens, J. Alfredo Freites, Karin L. Németh-Cahalan, Matthias Heyden, Douglas J. Tobias, James E. Hall, Tamir Gonen
Allosteric Mechanism Of Water Channel Gating By Ca2+–Calmodulin, Steve Reichow, Daniel M. Clemens, J. Alfredo Freites, Karin L. Németh-Cahalan, Matthias Heyden, Douglas J. Tobias, James E. Hall, Tamir Gonen
Chemistry Faculty Publications and Presentations
Calmodulin (CaM) is a universal regulatory protein that communicates the presence of calcium to its molecular targets and correspondingly modulates their function. This key signaling protein is important for controlling the activity of hundreds of membrane channels and transporters. However, our understanding of the structural mechanisms driving CaM regulation of full-length membrane proteins has remained elusive. In this study, we determined the pseudo-atomic structure of full-length mammalian aquaporin-0 (AQP0, Bos Taurus) in complex with CaM using electron microscopy to understand how this signaling protein modulates water channel function. Molecular dynamics and functional mutation studies reveal how CaM binding inhibits AQP0 …
Advances In Structural And Functional Analysis Of Membrane Proteins By Electron Crystallography, Goragot Wisedchaisri, Steve Reichow, Tamir Gonen
Advances In Structural And Functional Analysis Of Membrane Proteins By Electron Crystallography, Goragot Wisedchaisri, Steve Reichow, Tamir Gonen
Chemistry Faculty Publications and Presentations
Electron crystallography is a powerful technique for the study of membrane protein structure and function in the lipid environment. When well-ordered two-dimensional crystals are obtained the structure of both protein and lipid can be determined and lipid-protein interactions analyzed. Protons and ionic charges can be visualized by electron crystallography and the protein of interest can be captured for structural analysis in a variety of physiologically distinct states. This review highlights the strengths of electron crystallography and the momentum that is building up in automation and the development of high throughput tools and methods for structural and functional analysis of membrane …
Akap2 Anchors Pka With Aquaporin-0 To Support Ocular Lens Transparency, Matthew G. Gold, Steve Reichow, Susan E. O'Neill, Chad R. Weisbrod, Lorene K. Langeberg, James E. Bruce, Tamir Gonen, John D. Scott
Akap2 Anchors Pka With Aquaporin-0 To Support Ocular Lens Transparency, Matthew G. Gold, Steve Reichow, Susan E. O'Neill, Chad R. Weisbrod, Lorene K. Langeberg, James E. Bruce, Tamir Gonen, John D. Scott
Chemistry Faculty Publications and Presentations
A decline in ocular lens transparency known as cataract afflicts 90% of individuals by the age 70. Chronic deterioration of lens tissue occurs as a pathophysiological consequence of defective water and nutrient circulation through channel and transporter proteins. A key component is the aquaporin-0 (AQP0) water channel whose permeability is tightly regulated in healthy lenses. Using a variety of cellular and biochemical approaches we have discovered that products of the A-kinase anchoring protein 2 gene (AKAP2/AKAP-KL) form a stable complex with AQP0 to sequester protein kinase A (PKA) with the channel. This permits PKA phosphorylation of serine 235 within a …