Extended Data Fig. 9: Bowhead whale CIRBP RNA and protein sequence confer higher expression levels compared to human sequence.
From: Evidence for improved DNA repair in the long-lived bowhead whale
a, Amino acid sequence alignment between human and bowhead whale CIRBP using BLAST analysis. Bowhead whale specific variants are indicated. b, Structural models of human (left, pink) and bowhead whale (right, blue) CIRBP generated using SwissModel and AlphaFold. Side chains of amino acid residues that differ between species are shown, and the corresponding ribbon is highlighted in yellow in the whale model. All substitutions are located in the C-terminal disordered region, while the N-terminal RNA recognition motif (RRM) is conserved and structured. c, Evolution of bowhead whale CIRBP variants. Asterisks indicate the presence of bowhead whale-specific amino acid variants from. Variant positions are colour-coded according to their locations shown in a. d, Bowhead whale specific variants confer higher protein expression. Western blot analysis of CIRBP protein abundance in human cells overexpressing human CIRBP (hCIRBP), bowhead whale CIRBP (bwCIRBP), and reciprocal amino acid substitution mutants. H5BW is a human CIRBP with five bowhead whale substitutions. BW5H is a bowhead whale CIRBP with five human substitutions. Experiment repeated three times with similar results. e, Calculated codon adaptation index (CAI) values for CIRBP coding sequence variants.
