Figure 2.

(a) Amino acid sequence alignment of the HR domain in TnT polypeptides. Conserved Leu-s or hydrophobic residues in positions “a” and “d” of the HR units (“abcdefg”) are shaded. Amino acid residues Leu(L)²⁰³, Trp(W)²⁰⁴, Leu(L)²⁰⁷, and Arg(R)²¹⁴ of the human fast skeletal βTnT are marked for reference. The HR region is underlined. GenBank accession numbers for the TnT sequences in the multiple alignment are the following (from the top to bottom): P45378, P45379, P09742, P02642, P02641, P12618, P13805, D50867, U44759, U23523, U29082, and P19351. (b) Amino acid sequence alignment of the HR in TnI polypeptides. Conserved hydrophobic residues in positions “a” and “d” of each repeat are shaded. GenBank accession numbers for the TnI sequences in the multiple alignment are the following (from the top to bottom): P23693, P19429, P08057, L25721, X14190, P02644, U20111, Z66562, U40951, P36188, P05547, and 994895.