Fig. 1

Multiple sequence alignment of CBG protein sequences from mammals, chicken and Zebra Finch are created in MEGA 7.0 [84] using the ClustalW algorithms. Regions involved in steroid binding and release, including helix A (hA), helix D (hD), helix H (hH), β-sheet B (s2B, s3B, s4B, s5B) and RCL [18, 83], are shown. Residue numbering is defined as those in rat CBG sequence [18]. Residues whose side chains directly interact with cortisol in the crystal structures of rat CBG and Zebra Finch CBG, are marked by grey boxes. Specific residues in chicken and/or Zebra Finch CBGs different from those of mammalian CBGs are highlighted in red or magenta boxes, with other residues in mammals marked by boxes in different light colors. Consensus sequences for N-linked glycosylation are shown in black boxes. Homo sapiens, human; Pan troglodytes, Chimpanzee; Pongo abelii, Sumatran Orangutan; Nomascus leucogenys, White-cheeked Gibbon; Macaca mulatta, Rhesus Macaque; Rattus norvegicus, Brown Rat; Mus musculus, mouse; Equus caballus, horse; Bos taurus, cow; Loxodonta africana, African Elephant; Gallus gallus, chicken; Taeniopygia guttata, Zebra Finch