Unprecedented Intramolecular Association-Induced Fluorescence in Tryptophan-Conjugated Peptidomimetics

2019 ◽  
Vol 123 (14) ◽  
pp. 3112-3117
Author(s):  
Shreya Juneja ◽  
Hanuman Singh ◽  
Sayan Palui ◽  
Shruti Trivedi ◽  
Sharan S. Singh ◽  
...  
Keyword(s):  
Intramolecular Association

E-Homolupane Derivatives Substituted in Position 17 and 22a. 1H NMR, 13C NMR and IR Spectra

1995 ◽  
Vol 60 (4) ◽  
pp. 619-635 ◽  
Author(s):  
Václav Křeček ◽  
Stanislav Hilgard ◽  
Miloš Buděšínský ◽  
Alois Vystrčil
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Coupling Constants ◽  
Side Chain ◽  
Oxidation Reactions ◽  
H Nmr ◽  
Complete Assignment ◽  
Nmr Techniques ◽  
Intramolecular Association ◽  
C Nmr

A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy. The kind of intramolecular association of the 17α-hydroxy group was studied in connection with modification of the side chain and substitution in position 22a. Complete assignment of the hydrogen signals and most of the coupling constants was accomplished using a combination of 1D and 2D NMR techniques. The 1H and 13C NMR spectra are discussed.

The Mobility of Tryptophan and Dansyl Fluorophores in Labelled Poly(N-ethylacrylamide) and Poly(N-ethylmethacrylamide)

1993 ◽  
Vol 58 (10) ◽  
pp. 2383-2395 ◽  
Author(s):  
František Mikeš ◽  
Drahomír Výprachtický ◽  
Jan Pecka
Keyword(s):  
Conformational Changes ◽  
High Viscosity ◽  
Side Chains ◽  
Fluorescence Depolarization ◽  
Polymer Backbone ◽  
Short Side ◽  
Low Viscosity ◽  
Viscosity Range ◽  
Methylene Groups ◽  
Intramolecular Association

The mobility of tryptophan fluorophore in N-butyl-Nα-acetyltryptophanamide and in side chain of labelled poly(N-ethylacrylamide) and poly(N-ethylmethacrylamide) was investigated by the fluorescence depolarization method. The mobility of the fluorophore in the low-molecular-weight model is much higher than in side chains of the polymers. Different steric hindrance by the polymer backbone can explain the higher mobility of the fluorophore in poly(N-ethylacrylamide) and in poly(N-ethylmethacrylamide). The mobility of 5-dimethylamino-1-naphthalenesulfonamide (dansyl) fluorophore in side chains of labelled poly(N-ethylmethacrylamide) in the high-viscosity range increases with increasing number of methylene groups in side chains. The low-viscosity range, the rate s of conformational changes in short side chains (n = 2 - 7) are approximately constant and significantly decrease in long side chains (n = 10, 12). The drop in the rates is probably due to intramolecular association of the long hydrophobic chains in water.

scholarly journals An Intramolecular Association between Two Domains of the Protein Kinase Fused Is Necessary for Hedgehog Signaling

2004 ◽  
Vol 24 (23) ◽  
pp. 10397-10405 ◽  
Author(s):  
Manuel Ascano ◽  
David J. Robbins
Keyword(s):  
Signal Transduction ◽  
Protein Kinase ◽  
Hedgehog Signaling ◽  
Membrane Vesicles ◽  
Kinase Domain ◽  
Kinase Assay ◽  
Dependent Manner ◽  
Intramolecular Association

ABSTRACT The protein kinase Fused (Fu) is an integral member of the Hedgehog (Hh) signaling pathway. Although genetic studies demonstrate that Fu is required for the regulation of the Hh pathway, the mechanistic role that it plays remains largely unknown. Given our difficulty in developing an in vitro kinase assay for Fu, we reasoned that the catalytic activity of Fu might be highly regulated. Several mechanisms are known to regulate protein kinases, including self-association in either an intra- or an intermolecular fashion. Here, we provide evidence that Hh regulates Fu through intramolecular association between its kinase domain (ΔFu) and its carboxyl-terminal domain (Fu-tail). We show that ΔFu and Fu-tail can interact in trans, with or without the kinesin-related protein Costal 2 (Cos2). However, since the majority of Fu is found associated with Cos2 in vivo, we hypothesized that Fu-tail, which binds Cos2 directly, would be able to tether ΔFu to Cos2. We demonstrate that ΔFu colocalizes with Cos2 in the presence of Fu-tail and that this colocalization occurs on a subset of membrane vesicles previously characterized to be important for Hh signal transduction. Additionally, expression of Fu-tail in fu mutant flies that normally express only the kinase domain rescues the fu wing phenotype. Therefore, reestablishing the association between these two domains of Fu in trans is sufficient to restore Hh signal transduction in vivo. In such a manner we validate our hypothesis, demonstrating that Fu self-associates and is functional in an Hh-dependent manner. Our results here enhance our understanding of one of the least characterized, yet critical, components of Hh signal transduction.

scholarly journals Acidic phospholipids inhibit the intramolecular association between the N- and C-terminal regions of vinculin, exposing actin-binding and protein kinase C phosphorylation sites

1996 ◽  
Vol 314 (3) ◽  
pp. 827-832 ◽  
Author(s):  
John WEEKES ◽  
Simon T. BARRY ◽  
David R. CRITCHLEY
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Fusion Proteins ◽  
Phosphorylation Site ◽  
Actin Binding ◽  
Tail Region ◽  
Thrombin Cleavage ◽  
Kinase C ◽  
Intramolecular Association ◽  
Acidic Phospholipids

Chick vinculin polypeptides expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins have been used to identify the sites involved in the intramolecular association between the 90 kDa N-terminal head and the 30 kDa C-terminal tail region of the vinculin molecule. Fusion proteins spanning vinculin residues 1–258 and 1–398, immobilized on glutathione–agarose beads, were shown to bind a C-terminal vinculin polypeptide spanning residues 881–1066 (liberated from GST by thrombin cleavage). However, the C-terminal polypeptide did not bind to a fusion protein spanning residues 399–881 or to itself. Binding was dependent on residues 167–207 within the N-terminal polypeptide, a sequence also essential for talin binding. Conversely, the 90 kDa head polypeptide was shown to bind to residues 1029–1036 in the tail region of vinculin. The association of head and tail was inhibited by acidic, but not neutral, phospholipids. Pre-incubation of vinculin with acidic phospholipids exposed the binding site for F-actin and a phosphorylation site for protein kinase C. The phosphorylation site was located in the tail region of the vinculin molecule. These results raise the possibility that acidic phospholipids play a role in regulating the activity of vinculin and therefore the assembly of both cell–cell and cell–matrix adherens-type junctions.

scholarly journals Structure Elucidation of N-aryl-2-chloro-3-oxobutanamides with respect to intra- and intermolecular hydrogen bonding

2002 ◽  
Vol 2002 (1) ◽  
pp. 13-14 ◽  
Author(s):  
Petra Frohberg ◽  
Guntram Drutkowski ◽  
Christoph Wagner ◽  
Olaf Lichtenberger
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Solid State ◽  
Structure Elucidation ◽  
Intermolecular Hydrogen Bond ◽  
Carbonyl Oxygen ◽  
Intermolecular Hydrogen Bonding ◽  
Intramolecular Association

In general, N-aryl-2-chloro-3-oxobutanamides form in solid state an intermolecular hydrogen bond between the anilide hydrogen and the anilide carbonyl oxygen of a neighbouring molecule, which is disrupted in solution. An intramolecular association could not be detected.

scholarly journals Structural Dynamics of α-Actinin-Vinculin Interactions

2005 ◽  
Vol 25 (14) ◽  
pp. 6112-6122 ◽  
Author(s):  
Philippe R. J. Bois ◽  
Robert A. Borgon ◽  
Clemens Vonrhein ◽  
Tina Izard
Keyword(s):  
Conformational Changes ◽  
Structural Changes ◽  
Focal Adhesions ◽  
Tail Domain ◽  
Spectrin Repeat ◽  
Helical Bundle ◽  
Adhesion Junctions ◽  
Intramolecular Association ◽  
Α Helix ◽  
Opening Up

ABSTRACT α-Actinin and vinculin orchestrate reorganization of the actin cytoskeleton following the formation of adhesion junctions. α-Actinin interacts with vinculin through the binding of an α-helix (αVBS) present within the R4 spectrin repeat of its central rod domain to vinculin's N-terminal seven-helical bundle domain (Vh1). The Vh1:αVBS structure suggests that αVBS first unravels from its buried location in the triple-helical R4 repeat to allow it to bind to vinculin. αVBS binding then induces novel conformational changes in the N-terminal helical bundle of Vh1, which disrupt its intramolecular association with vinculin's tail domain and which differ from the alterations in Vh1 provoked by the binding of talin. Surprisingly, αVBS binds to Vh1 in an inverted orientation compared to the binding of talin's VBSs to vinculin. Importantly, the binding of αVBS and talin's VBSs to vinculin's Vh1 domain appear to also trigger distinct conformational changes in full-length vinculin, opening up distant regions that are buried in the inactive molecule. The data suggest a model where vinculin's Vh1 domain acts as a molecular switch that undergoes distinct structural changes provoked by talin and α-actinin binding in focal adhesions versus adherens junctions, respectively.

Sign in / Sign up

Export Citation Format

Share Document