ErbB3 is required for normal cerebellar and cardiac development: a comparison with ErbB2- and heregulin-deficient mice

Open Access
Publisher Website
Google Scholar
Abstract
Heregulins bind directly to ErbB3 and ErbB4 receptors, leading to multiple dimerization possibilities including heterodimerization with the ErbB2 receptor. We have generated ErbB3-, ErbB2- and heregulin-deficient mice to assess their roles in development and differentiation. Heregulin(−/−) and ErbB2(−/−) embryos died on E10.5 due to a lack of cardiac ventricular myocyte differentiation; ErbB3(−/−) embryos survived until E13.5 exhibiting cardiac cushion abnormalities leading to blood reflux through defective valves. In ErbB3(−/−) embryos, the midbrain/hindbrain region was strikingly affected, with little differentiation of the cerebellar plate. Cranial ganglia defects, while present in all three nulls, were less severe in ErbB3(−/−) embryos. The cranial ganglia defects, along with a dramatic reduction in Schwann cells, enteric ganglia and adrenal chromaffin cells, suggests a generalized effect on the neural crest. Numerous organs, including the stomach and pancreas also exhibited anomalous development.