Figure 5.

Schematic of the cardiac TnT gene, indicating sites of HCM-causing mutations. The position of the three mutations investigated in this work (Ile79Asn, Arg92Gln, and ΔGlu160) are indicated, as is the splice site mutation that results in the truncated cardiac TnT that we have characterized (8). (The intron 15^G→A mutation inactivates a 5′ splice donor site leading to either skipping of exon 15 or activation of a cryptic splice site.) The three mutations presented herein all lie within a region that interacts with α-tropomyosin (αTM) in a calcium insensitive manner (30). The more C-terminal region of TnT interacts in a calcium-sensitive manner with tropomyosin and interacts with the rest of the troponin complex (TnI and TnC).