Codon selection reduces GC content bias in nucleic acids encoding for intrinsically disordered proteins.

Codon selection reduces GC content bias in nucleic acids encoding for intrinsically disordered proteins.
Cell Mol Life Sci. 2019 Jun 07;:
Authors: Oldfield CJ, Peng Z, Uversky VN, Kurgan L
Abstract
Protein-coding nucleic acids exhibit composition and codon biases between sequences coding for intrinsically disordered regions (IDRs) and those coding for structured regions. IDRs are regions of proteins that are folding self-insufficient and which function without the prerequisite of folded structure. Several authors have investigated composition bias or codon selection in regions encoding for IDRs, primarily in Eukaryota, and concluded that elevated GC content is the result of the biased amino acid composition of IDRs. We substantively extend previous work by examining GC content in regions encoding IDRs, from 44 species in Eukaryota, Archaea, and Bacteria, spanning a wide range of GC content. We confirm that regions coding for IDRs show a significantly elevated GC content, even across all domains of life. Although this is largely attributable to the amino acid composition bias of IDRs, we show that this bias is independent of the overall GC content and, most importantly, we are the first to observe that GC content bias in IDRs is significantly different than expected from IDR amino acid composition alone. We empirically find compensatory codon selection that reduces the observed GC content bias in IDRs. This selection is dependent on t...

Source: Cellular and Molecular Life Sciences : CMLS - June 6, 2019 Category: Cytology Authors: Oldfield CJ, Peng Z, Uversky VN, Kurgan L Tags: Cell Mol Life Sci Source Type: research