Structural Basis of the Selective Activation of Enzyme Isoforms: Allosteric Response to Activators of β1- and β2-Containing AMPK Complexes

Migraine headache has become global pandemics and is the number one reason of work day loss. The most common drugs for anti-migraine are the triptan class of drugs that are agonists for serotonin receptors 5-HT1B and 5-HT1D. However, these drugs have side effects related to vasoconstriction that could have fatal consequences of ischemic heart disease and myocardial infarction. Lasmiditan is a new generation of anti-migraine drug that selectively binds to the serotonin receptor 5-HT1F due to its advantage over the tripan class of anti-migraine drugs. Here we report the cryo-EM structure of the 5-HT1F in complex with Lasmiditan and the inhibitory G protein heterotrimer. The structure reveals the mechanism of 5-HT1F-selective activation by Lasmiditan and provides a template for rational design of anti-migraine drugs.

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Structural basis for the selective activation of Rho GTPases by Dbl exchange factors

Natural Structural Biology ◽

10.1038/nsb796 ◽

2002 ◽

Vol 9 (6) ◽

pp. 468-475 ◽

Cited By ~ 151

Author(s):

Jason T. Snyder ◽

David K. Worthylake ◽

Kent L. Rossman ◽

Laurie Betts ◽

Wendy M. Pruitt ◽

...

Keyword(s):

Rho Gtpases ◽

Structural Basis ◽

Selective Activation

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Structural Basis for the Metal-Selective Activation of the Manganese Transport Regulator ofBacillus subtilis†,‡

Biochemistry ◽

10.1021/bi0524215 ◽

2006 ◽

Vol 45 (11) ◽

pp. 3493-3505 ◽

Cited By ~ 44

Author(s):

Joseph I. Kliegman ◽

Sarah L. Griner ◽

John D. Helmann ◽

Richard G. Brennan ◽

Arthur Glasfeld

Keyword(s):

Structural Basis ◽

Ofbacillus Subtilis ◽

Selective Activation ◽

Manganese Transport Regulator ◽

Manganese Transport

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Organization of tight junctions in the choroid plexus epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100082546 ◽

1978 ◽

Vol 36 (2) ◽

pp. 336-337

Author(s):

B. Van Deurs ◽

J. K. Koehler

Keyword(s):

Choroid Plexus ◽

Present Report ◽

Freeze Fracture ◽

Barrier Properties ◽

Cell Junctions ◽

Structural Basis ◽

Apical Surface ◽

Choroid Plexus Epithelium ◽

Solid Nitrogen ◽

Special Composition

The choroid plexus epithelium constitutes a blood-cerebrospinal fluid (CSF) barrier, and is involved in regulation of the special composition of the CSF. The epithelium is provided with an ouabain-sensitive Na/K-pump located at the apical surface, actively pumping ions into the CSF. The choroid plexus epithelium has been described as “leaky” with a low transepithelial resistance, and a passive transepithelial flux following a paracellular route (intercellular spaces and cell junctions) also takes place. The present report describes the structural basis for these “barrier” properties of the choroid plexus epithelium as revealed by freeze fracture.Choroid plexus from the lateral, third and fourth ventricles of rats were used. The tissue was fixed in glutaraldehyde and stored in 30% glycerol. Freezing was performed either in liquid nitrogen-cooled Freon 22, or directly in a mixture of liquid and solid nitrogen prepared in a special vacuum chamber. The latter method was always used, and considered necessary, when preparations of complementary (double) replicas were made.

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High resolution spot scan imaging of frozen, hydrated actin bundles with 400kV electrons

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122964 ◽

1992 ◽

Vol 50 (1) ◽

pp. 512-513

Author(s):

J. Jakana ◽

M.F. Schmid ◽

P. Matsudaira ◽

W. Chiu

Keyword(s):

High Resolution ◽

Binding Proteins ◽

Actin Binding ◽

Eukaryotic Cells ◽

Dimensional Structure ◽

Structural Basis ◽

Actin Bundle ◽

Actin Bundles ◽

3 Dimensional ◽

Macromolecular Assembly

Actin is a protein found in all eukaryotic cells. In its polymerized form, the cells use it for motility, cytokinesis and for cytoskeletal support. An example of this latter class is the actin bundle in the acrosomal process from the Limulus sperm. The different functions actin performs seem to arise from its interaction with the actin binding proteins. A 3-dimensional structure of this macromolecular assembly is essential to provide a structural basis for understanding this interaction in relationship to its development and functions.

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Electron Microscopy and image reconstruction reveal the structural basis for spectrin's elastic properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122952 ◽

1992 ◽

Vol 50 (1) ◽

pp. 510-511

Author(s):

Amy M. McGough ◽

Robert Josephs

Keyword(s):

Electron Microscopy ◽

Elastic Properties ◽

Conformational Changes ◽

Quaternary Structure ◽

Three Dimensional ◽

Membrane Skeleton ◽

Projection Algorithm ◽

Structural Basis ◽

Iterative Approximation ◽

Membrane Skeletons

The remarkable deformability of the erythrocyte derives in large part from the elastic properties of spectrin, the major component of the membrane skeleton. It is generally accepted that spectrin's elasticity arises from marked conformational changes which include variations in its overall length (1). In this work the structure of spectrin in partially expanded membrane skeletons was studied by electron microscopy to determine the molecular basis for spectrin's elastic properties. Spectrin molecules were analysed with respect to three features: length, conformation, and quaternary structure. The results of these studies lead to a model of how spectrin mediates the elastic deformation of the erythrocyte.Membrane skeletons were isolated from erythrocyte membrane ghosts, negatively stained, and examined by transmission electron microscopy (2). Particle lengths and end-to-end distances were measured from enlarged prints using the computer program MACMEASURE. Spectrin conformation (straightness) was assessed by calculating the particles’ correlation length by iterative approximation (3). Digitised spectrin images were correlation averaged or Fourier filtered to improve their signal-to-noise ratios. Three-dimensional reconstructions were performed using a suite of programs which were based on the filtered back-projection algorithm and executed on a cluster of Microvax 3200 workstations (4).

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Electron diffraction detection of ordliking in annealed PbTe thin film

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178227 ◽

1990 ◽

Vol 48 (4) ◽

pp. 1018-1019

Author(s):

Karimat El-Sayed

Keyword(s):

Thin Film ◽

Electron Diffraction ◽

Lead Telluride ◽

Structural Basis ◽

Face Centered Cubic ◽

X Ray ◽

Polycrystalline Thin Films ◽

Stage Process ◽

Diffraction Patterns ◽

Face Centered

Lead telluride is an important semiconductor of many applications. Many Investigators showed that there are anamolous descripancies in most of the electrophysical properties of PbTe polycrystalline thin films on annealing. X-Ray and electron diffraction studies are being undertaken in the present work in order to explain the cause of this anamolous behaviour.Figures 1-3 show the electron diffraction of the unheated, heated in air at 100°C and heated in air at 250°C respectively of a 300°A polycrystalline PbTe thin film. It can be seen that Fig. 1 is a typical [100] projection of a face centered cubic with unmixed (hkl) indices. Fig. 2 shows the appearance of faint superlattice reflections having mixed (hkl) indices. Fig. 3 shows the disappearance of thf superlattice reflections and the appearance of polycrystalline PbO phase superimposed on the [l00] PbTe diffraction patterns. The mechanism of this three stage process can be explained on structural basis as follows :

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Ubiquinone-BODIPY nanoparticles for tumor redox-responsive fluorescence imaging and photodynamic activity

Journal of Materials Chemistry B ◽

10.1039/d0tb02529a ◽

2021 ◽

Author(s):

Byunghee Hwang ◽

Tae-Il Kim ◽

Hyunjin Kim ◽

Sungjin Jeon ◽

Yongdoo Choi ◽

...

Keyword(s):

Fluorescence Imaging ◽

Selective Activation ◽

Turn On ◽

Intracellular Environment ◽

Redox Responsive ◽

Photodynamic Activity

A ubiquinone-BODIPY photosensitizer self-assembles into nanoparticles (PS-Q-NPs) and undergoes selective activation within the highly reductive intracellular environment of tumors, resulting in “turn-on” fluorescence and photosensitizing activities.

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