Transcript chapter_14

Figure 14.17 Rescue of cardiac malformations in mutant embryos lacking the Id genes. (A) The mutant hearts have a thin
myocardial wall, impaired ventricular trabeculation, endocardial cushion defects, outflow tract atresia and ventricular septal
defects (VSD). Box illustrates reduced myocardial cell proliferation and a discontinuous endocardial cell lining. (B) Wild-type
(wt) ESCs transgenic for lacZ effected complete rescue of the hearts when injected into mutant blastocysts (left), but only
partial rescue when injected intraperitoneally into the mothers, suggesting that short-range and long-range Id-dependent
signals are required for normal heart development. The short-range signal was identified as Wnt5a and the long-range signal as
IGF-1. Reproduced with permission from Chien et al., ES cells to the rescue. Science 306:239–240. Copyright 2004, AAAS.
Copyright © 2012 Elsevier Inc. All rights reserved.