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Structure of an Unfolding Intermediate of an RRM Domain of ETR-3 Reveals Its Native-like Fold.

ABSTRACT: Prevalence of one or more partially folded intermediates during protein unfolding with different secondary and ternary conformations has been identified as an integral character of protein unfolding. These transition-state species need to be characterized structurally for elucidation of their folding pathways. We have determined the three-dimensional structure of an intermediate state with increased conformational space sampling under urea-denaturing condition. The protein unfolds completely at 10 M urea but retains residual secondary structural propensities with restricted motion. Here, we describe the native state, observable intermediate state, and unfolded state for ETR-3 RRM-3, which has canonical RRM fold. These observations can shed more light on unfolding events for RRM-containing proteins.

SUBMITTER: Bhatt H

PROVIDER: S-EPMC6976808 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Structure of an Unfolding Intermediate of an RRM Domain of ETR-3 Reveals Its Native-like Fold.

Bhatt Harshesh H Ganguly Akshay Kumar AK Sharma Sonam S Kushwaha Gajraj Singh GS Firoz Khan Mohammad M Sen Sobhan S Bhavesh Neel Sarovar NS

Biophysical journal 20191206 2

Prevalence of one or more partially folded intermediates during protein unfolding with different secondary and ternary conformations has been identified as an integral character of protein unfolding. These transition-state species need to be characterized structurally for elucidation of their folding pathways. We have determined the three-dimensional structure of an intermediate state with increased conformational space sampling under urea-denaturing condition. The protein unfolds completely at ...[more]

PMID: 31866002

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