Using deep mutagenesis to understand genetic and physical interactions

The first aim of this thesis was to tackle a core question in biology—to understand how large numbers of mutations combine together to influence phenotypes. In order to do so, we built a combinatorially-complete library of naturally occurring variants in a yeast tRNA. For the first time in any gene,...

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Detalles Bibliográficos
Autor: Domingo Espinós, Júlia
Tipo de recurso: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/668731
Acceso en línea:http://hdl.handle.net/10803/668731
Access Level:acceso abierto
Palabra clave:Genetic interactions
tRNA
Protein-protein interactions
Mutagenesis
Genetics
Interaccions genètiques
RNAt
Interaccions de proteïnes
Mutagènesi
Genètica
575
Descripción
Sumario:The first aim of this thesis was to tackle a core question in biology—to understand how large numbers of mutations combine together to influence phenotypes. In order to do so, we built a combinatorially-complete library of naturally occurring variants in a yeast tRNA. For the first time in any gene, we could quantify the extent of which both the effects of individual mutations and the interactions between pairs of mutations change across a large number of closely-related genotypes. We found that all mutations switch from beneficial to detrimental effects and all interactions switch from positive to negative in different backgrounds. Secondly, with the use of systematic mutagenesis, protein complementation assays and deep sequencing, we developed a new experimental methodology to map the interaction interfaces of physically interacting proteins at amino acid resolution. The approach works by quantifying the effects of mutations on both protein binding and stability, resulting in a high resolution map of an interaction interface.