RESUMEN
Serotonin (5-hydroxytryptamine; 5-HT) signaling through the 5-HT(2C) receptor (5-HT(2C)R) is essential in normal physiology, whereas aberrant 5-HT(2C)R function is thought to contribute to the pathogenesis of multiple neural disorders. The 5-HT(2C)R interacts with specific protein partners, but the impact of such interactions on 5-HT(2C)R function is poorly understood. Here, we report convergent cellular and behavioral data that the interaction between the 5-HT(2C)R and protein phosphatase and tensin homolog (PTEN) serves as a regulatory mechanism to control 5-HT(2C)R-mediated biology but not that of the closely homologous 5-HT(2A)R. A peptide derived from the third intracellular loop of the human 5-HT(2C)R [3L4F (third loop, fourth fragment)] disrupted the association, allosterically augmented 5-HT(2C)R-mediated signaling in live cells, and acted as a positive allosteric modulator in rats in vivo. We identified the critical residues within an 8 aa fragment of the 3L4F peptide that maintained efficacy (within the picomolar range) in live cells similar to that of the 3L4F peptide. Last, molecular modeling identified key structural features and potential interaction sites of the active 3L4F peptides against PTEN. These compelling data demonstrate the specificity and importance of this protein assembly in cellular events and behaviors mediated by 5-HT(2C)R signaling and provide a chemical guidepost to the future development of drug-like peptide or small-molecule inhibitors as neuroprobes to study 5-HT(2C)R allostery and therapeutics for 5-HT(2C)R-mediated disorders.
Asunto(s)
Modelos Moleculares , Fosfohidrolasa PTEN/química , Fosfohidrolasa PTEN/metabolismo , Receptor de Serotonina 5-HT2C/química , Receptor de Serotonina 5-HT2C/metabolismo , Transducción de Señal/fisiología , Secuencia de Aminoácidos , Animales , Humanos , Immunoblotting , Inmunoprecipitación , Masculino , Datos de Secuencia Molecular , Actividad Motora/fisiología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Ratas , Ratas Sprague-Dawley , Serotonina/metabolismo , TransfecciónRESUMEN
This paper reports a study to find small peptide substrates for the important virulence factor of Yersinia pestis, plasminogen activator, Pla. The method used to find small substrates for this protease is reported along with studies examining the ability of these peptides to inhibit activity of the enzyme. Through the use of parallel synthesis and positional scanning, small tripeptides were identified that are viable substrates for the protease.
Asunto(s)
Proteínas Bacterianas/antagonistas & inhibidores , Péptidos/síntesis química , Péptidos/farmacología , Activadores Plasminogénicos/antagonistas & inhibidores , Inhibidores de Proteasas/síntesis química , Inhibidores de Proteasas/farmacología , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Fluorometría , Cinética , Datos de Secuencia Molecular , Oligopéptidos/síntesis química , Oligopéptidos/química , Oligopéptidos/farmacología , Péptidos/química , Activadores Plasminogénicos/química , Activadores Plasminogénicos/metabolismo , Inhibidores de Proteasas/química , Conformación Proteica , Relación Estructura-Actividad , Especificidad por Sustrato , Yersinia pestis/enzimologíaRESUMEN
This paper reports the preparation of a library of unsymmetrical ureas based on 8-azabicyclo[3.2.1]octane scaffold. The reported synthetic route uses nortropane-8-carbonyl chlorides as key intermediates that, when treated with a slight excess of amine, give the corresponding ureas in high yield (129 examples).
Asunto(s)
Técnicas Químicas Combinatorias/métodos , Tropanos/química , Urea/síntesis química , Aminas/química , Hidrocarburos Clorados/química , Modelos Químicos , Peso Molecular , Nortropanos/química , Solubilidad , Solventes/químicaRESUMEN
[reaction: see text] Work toward the development of a bis-phosphine ligand system for the palladium-catalyzed desymmetrization of meso-diols is reported. A parallel approach using phosphine-containing amino acids and a "representational search" was taken to find a polymer-supported catalyst system. The selectivities reported are comparable to many other polymer-bound asymmetric catalysts.
Asunto(s)
Alcoholes/química , Ciclopentanos/química , Compuestos Organoplatinos/química , Secuencia de Aminoácidos , Aminoácidos/química , Catálisis , Oligopéptidos/química , Fosfinas/química , Estructura Secundaria de Proteína , EstereoisomerismoRESUMEN
[reaction: see text] Work toward the development of a bisphosphine ligand system for the palladium-catalyzed addition to cyclic allyl acetates is reported. A parallel approach using phosphine-containing amino acids in conjunction with natural amino acids was used to develop a selective ligand system. The ligand system was examined while attached to the polymer support as well as in solution. Selectivites with the difficult substrate 3-acetoxycyclopentene of up to 95% ee are reported.
Asunto(s)
Aminoácidos/química , Oligopéptidos/química , Compuestos Organometálicos/química , Paladio/química , Fosfinas/química , Acetatos/química , Secuencia de Aminoácidos , Catálisis , Ciclopentanos/química , Ligandos , Modelos Moleculares , Estructura Secundaria de Proteína , Estereoisomerismo , Relación Estructura-ActividadAsunto(s)
Péptidos/farmacología , Quinasas Asociadas a rho/antagonistas & inhibidores , Adenosina Trifosfato/metabolismo , Animales , Dominio Catalítico/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Células HeLa , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/metabolismo , Ratones , Ratones Endogámicos C57BL , Células 3T3 NIHRESUMEN
Combinatorial chemistry has recently burst on the scene as a valuable tool for the discovery of new drug candidates. The ability to synthesize hundreds of compounds for screening is a useful complement to rational drug design. There are many similarities between the design of new therapeutic agents and the development of new asymmetric ligands, the most important of which is the limitation of a rational design strategy. For this reason a program was begun that would allow the use of combinatorial technology in the development of new ligands for transition metal catalyzed asymmetric reactions. Because of the large number of catalytic reactions they are involved in the system was based around phosphine ligands. This paper reports the synthesis of phosphine derivatives of alanine, proline, and the aromatic amino acids tyrosine and hydroxyphenylglycine. Examples of the use of these amino acids in the synthesis of peptides possessing helical and beta-turn secondary structures are presented. Metal complexes of these peptide-based ligands are used in hydrogenation and alkylation reactions.
Asunto(s)
Aminoácidos/síntesis química , Diseño de Fármacos , Péptidos/síntesis química , Fosfinas/síntesis química , Aminoácidos/química , Ligandos , Estructura Molecular , Paladio/química , Péptidos/química , Fosfinas/química , Estructura Secundaria de Proteína , Rodio/químicaRESUMEN
We have been actively involved in the development of parallel approaches for the discovery of phosphine ligands. Our approach has been based on the incorporation of phosphine-containing amino acids into peptide sequences that are designed to have stable secondary structures. We have examined helical and turn secondary structures and have reported that alkylation of cyclopentenyl acetate with dimethylmalonate can be catalyzed in high enantiomeric excess (ee) with a beta-turn-based ligand. The importance of the peptide secondary structure was demonstrated through the synthesis of a series of peptide ligands where the nature of the turn-forming residues was probed. Additionally, other turn-forming units and a variety of different phosphine-containing amino acids have been examined for their ability to control the selectivity of the allylation reaction. This paper reports the results obtained through the examination of different turn motifs as well as different phosphine substitutions on the "best" turn sequence, Pps-Pro-d-Xxx-Pps.