Casq1 and Casq2 sequence alignment of regions containing post-translational modifications (from Lys301 to the C-terminus). Asterisks indicate conserved residues, and colons indicate conserved substitutions. The eukaryotic N-linked glycosylation consensus sequence, conserved between Casq1 and Casq2, is highlighted in green, and the glycosylated residue, Asn316, is emphasized with a box. (a) Sequence alignment of bovine Casq1 (btCasq1), canine Casq1 (cfCasq1), human Casq1 (hsCasq1), mouse Casq1 (mmCasq1), rabbit Casq1 (ocCasq1) and rat Casq1 (rnCasq1); (b) sequence alignment of the cardiac isoforms of the same species. The serine residues boxed and highlighted in yellow are the putative phosphorylation sites in the Casq2 C-terminal tails (Glu354 to the C-terminal Glu). The residues highlighted in blue are the remaining non-acidic residues, which the Casq1 C-terminal tail does not contain. Canine Casq2 has a third serine residue, which may be a third phosphorylation site, in its C-terminal tail.