RESUMEN
Targeted protein degradation (TPD) has emerged in the past decade as a major new drug modality to remove intracellular proteins with bispecific small molecules that recruit the protein of interest (POI) to an E3 ligase for degradation in the proteasome. Unlike classic occupancy-based drugs, intracellular TPD (iTPD) eliminates the target and works catalytically, and so can be more effective and sustained, with lower dose requirements. Recently, this approach has been expanded to the extracellular proteome, including both secreted and membrane proteins. Extracellular targeted protein degradation (eTPD) uses bispecific antibodies, conjugates or small molecules to degrade extracellular POIs by trafficking them to the lysosome for degradation. Here, we focus on recent advances in eTPD, covering degrader systems, targets, molecular designs and parameters to advance them. Now almost any protein, intracellular or extracellular, is addressable in principle with TPD.
Asunto(s)
Proteínas de la Membrana , Complejo de la Endopetidasa Proteasomal , Humanos , Proteolisis , Descubrimiento de Drogas , Ubiquitina-Proteína LigasasRESUMEN
The loops of modular polyketide synthases (PKSs) serve diverse functions but are largely uncharacterized. They frequently contain amino acid repeats resulting from genetic events such as slipped-strand mispairing. Determining the tolerance of loops to amino acid changes would aid in understanding and engineering these multidomain molecule factories. Here, tandem repeats in the DNA encoding 949 modules within 129 cis-acyltransferase PKSs were cataloged, and the locations of the corresponding amino acids within the module were identified. The most frequently inserted interdomain loop corresponds with the updated module boundary immediately downstream of the ketosynthase (KS), while the loops bordering the dehydratase are nearly intolerant to such insertions. From the 949 modules, no repetitive sequence loop insertions are located within ACP, and only 2 reside within KS, indicating the sensitivity of these domains to alteration.
Asunto(s)
Proteína Transportadora de Acilo/química , Aciltransferasas/química , Bacterias/enzimología , Proteínas Bacterianas/química , Sintasas Poliquetidas/química , Policétidos/metabolismo , Proteína Transportadora de Acilo/clasificación , Proteína Transportadora de Acilo/genética , Proteína Transportadora de Acilo/metabolismo , Aciltransferasas/clasificación , Aciltransferasas/genética , Aciltransferasas/metabolismo , Secuencia de Aminoácidos , Bacterias/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Cinética , Modelos Moleculares , Sintasas Poliquetidas/clasificación , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Policétidos/química , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , TermodinámicaRESUMEN
Modular polyketide synthases (PKSs) are enzymatic assembly lines that fuse carbon fragments into complex chiral products. Here, their synthetic logic is employed to chemoenzymatically generate two-stereocenter triketides. Each of the four stereoisomers was constructed in a stereocontrolled manner using C-acylation and two PKS ketoreductases possessing opposite stereoselectivities.