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Permitir la expansión del código genético y la macrociclado de péptidos en la visualización de ARNm a través de una
Sabrina E Iskandar1,2, Jarrett M Pelton1,2, Elizaveta T Wick3,4
1Division of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Journal of the American Chemical Society
|January 11, 2023
Resumen
Este estudio introduce un nuevo método que utiliza sintetasas de aminoacil-tRNA ortogonales (ORS) para crear diversas bibliotecas de péptidos para el descubrimiento de fármacos. Este enfoque permite la identificación de potentes ligantes de péptidos para objetivos terapéuticos.
Área de la Ciencia:
- La bioquímica
- Biología molecular
- Descubrimiento de drogas
Sus antecedentes:
- La visualización de ARN mensajero (ARNm) es una técnica poderosa para identificar aglutinantes de péptidos contra objetivos terapéuticos.
- La expansión de la diversidad química de estas bibliotecas es crucial para el descubrimiento de peptídeos ligandos clínicamente relevantes.
- Las sintetasas de aminoacil-tRNA ortogonales (ORS) están poco exploradas para aplicaciones de traducción in vitro (IVT) y de visualización de ARNm.
Objetivo del estudio:
- Investigar la utilidad de los ORS promiscuos para expandir la diversidad química en las bibliotecas de visualización de ARNm.
- Demostrar la incorporación de aminoácidos no canónicos y la subsiguiente macrociclización dentro de la muestra de ARNm.
- Identificar nuevos aglutinantes de péptidos para la deubiquitinasa USP15.
Principales métodos:
- Utilizó el ORS *p*-CNF-RS promiscuo para incorporar aminoácidos no canónicos, incluida la *p*-cianopirilalanina (*p*-CNpyrA), en proteínas a través de la supresión del codón ámbar durante la TIV.
- Diseñó una nueva estrategia de macrociclado de piridina-tiazolina (pyr-thn) dentro del marco de visualización de ARNm.
- Se realizaron selecciones contra la deubiquitinasa USP15 utilizando el método de macrociclado de piretano.
Principales resultados:
- Incorporó con éxito el nuevo aminoácido *p*-CNpyrA utilizando *p*-CNF-RS en el IVT.
- Se ha demostrado la viabilidad de la macrociclación de piretano en la visualización de ARNm.
- Se ha identificado un potente y selectivo aglutinante de péptidos macrocíclicos para la USP15.
Conclusiones:
- Los ORS promiscuos pueden expandir efectivamente la diversidad de las cadenas laterales en las bibliotecas de visualización de ARNm.
- La macrociclación de piretano desarrollada proporciona una novedad estructural para el descubrimiento de un aglutinante peptídico mejorado.
- Este enfoque avanza en el descubrimiento de fármacos peptídicos al permitir la identificación de enlaces específicos y potentes para objetivos terapéuticos.
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