|
Figure 3 Dilated Cardiomyopathy could be conditionally induced to occur in the transgenic zebrafish. Zebrafish transgenic line Tg(cmlc2:tetON-cTnc-antisence) was generated by Tsai’s lab, in which the antisense RNA strand of cardiac Troponin C (cTnC) gene and myocardium-specific GFP mRNA were conditionally induced to synthesize simultaneously in the myocardial cells of the heart; due to this, both directional transcriptions were driven by the promoter of cardiac myosin light chain 2 gene (cmlc2) under the Tet-On control system [114]. The heart shape (upper panel of left figures) and heartbeat (lower panel of left figures) were apparent normally in the embryos derived from this transgenic line without treatment of Doxycline (DOX) (control). However, when these embryos were treated with DOX, the dilated cardiomyopathy of heart shape occurred (upper panel of right figures), which was able to be observed under confocal microscope, and arrhythmic heart-beating was also detected (lower panel of right figures). These symptoms shown on zebrafish caused by knocking down of cTnC were similar to those of human incomplete atrio-ventricular conduction blocking disease.