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Updated: Apr 26, 2026
Echocardiographic and Histological Examination of Cardiac Morphology in the Mouse
Published on: October 26, 2017
Targeted inactivation of Cerberus like-2 leads to left ventricular cardiac hyperplasia and systolic dysfunction in
Ana Carolina Araújo1, Sara Marques2, José António Belo3
1Laboratory of Embryology and Genetic Manipulation, Regenerative Medicine Program, Departamento de Ciências Biomédicas e Medicina, Universidade do Algarve, Campus de Gambelas, Faro, Portugal; IBB - Institute for Biotechnology and Bioengineering, Centro de Biomedicina Molecular e Estrutural, Universidade do Algarve, Campus de Gambelas, Faro, Portugal; PhD Program in Biomedical Sciences, Universidade do Algarve, Campus de Gambelas, Faro, Portugal.
Abstract:
Previous analysis of the Cerberus like 2 knockout (Cerl2-/-) mouse revealed a significant mortality during the first day after birth, mostly due to cardiac defects apparently associated with randomization of the left-right axis. We have however, identified Cerl2-associated cardiac defects, particularly a large increase in the left ventricular myocardial wall in neonates that cannot be explained by laterality abnormalities. Therefore, in order to access the endogenous role of Cerl2 in cardiogenesis, we analyzed the embryonic and neonatal hearts of Cerl2 null mutants that did not display a laterality phenotype. Neonatal mutants obtained from the compound mouse line Cer2-/-::Mlc1v-nLacZ24+, in which the pulmonary ventricle is genetically marked, revealed a massive enlargement of the ventricular myocardium in animals without laterality defects. Echocardiography analysis in Cerl2-/- neonates showed a left ventricular systolic dysfunction that is incompatible with a long lifespan. We uncovered that the increased ventricular muscle observed in Cerl2-/- mice is caused by a high cardiomyocyte mitotic index in the compact myocardium which is mainly associated with increased Ccnd1 expression levels in the left ventricle at embryonic day (E) 13. Interestingly, at this stage we found augmented left ventricular expression of Cerl2 levels when compared with the right ventricle, which may elucidate the regionalized contribution of Cerl2 to the left ventricular muscle formation. Importantly, we observed an increase of phosphorylated Smad2 (pSmad2) levels in embryonic (E13) and neonatal hearts indicating a prolonged TGFβs/Nodal-signaling activation. Concomitantly, we detected an increase of Baf60c levels, but only in Cerl2-/- embryonic hearts. These results indicate that independently of its well-known role in left-right axis establishment Cerl2 plays an important role during heart development in the mouse, mediating Baf60c levels by exerting an important control of the TGFβs/Nodal-signaling pathway.
Insights
The Cerberus like 2 (Cerl2) gene is crucial for mouse heart development, controlling cardiomyocyte proliferation and ventricular growth independently of left-right axis formation. Loss of Cerl2 leads to cardiac defects and systolic dysfunction.
Area of Science:
- Developmental Biology
- Cardiovascular Biology
- Genetics
Background:
- Previous studies linked Cerberus like 2 knockout (Cerl2-/-) mice to mortality from cardiac defects and left-right axis randomization.
- However, Cerl2 deficiency also causes cardiac abnormalities unrelated to laterality, suggesting a distinct role in heart development.
Purpose of the Study:
- To investigate the endogenous role of Cerberus like 2 (Cerl2) in cardiogenesis, independent of its known function in left-right axis establishment.
- To analyze the cardiac phenotypes in Cerl2 null mutants that do not exhibit laterality defects.
Main Methods:
- Analysis of embryonic and neonatal hearts from Cerl2 null mutant mice, including a compound line with genetic marking of the pulmonary ventricle.
- Echocardiography was performed on Cerl2-/- neonates to assess cardiac function.
- Molecular analyses included examining cardiomyocyte mitotic index, Ccnd1 expression, phosphorylated Smad2 (pSmad2) levels, and Baf60c levels.
Main Results:
- Cerl2-/- mice without laterality defects exhibited massive ventricular myocardium enlargement and left ventricular systolic dysfunction.
- Increased ventricular muscle mass was attributed to a high cardiomyocyte mitotic index, linked to elevated Ccnd1 expression in the left ventricle at embryonic day 13.
- Prolonged TGFβs/Nodal-signaling activation (indicated by increased pSmad2) and elevated Baf60c levels were observed in Cerl2-/- embryonic hearts.
Conclusions:
- Cerberus like 2 (Cerl2) plays a significant role in mouse heart development, controlling ventricular muscle formation.
- Cerl2 regulates cardiomyocyte proliferation and ventricular growth independently of left-right axis establishment.
- Cerl2 mediates Baf60c levels and controls TGFβs/Nodal-signaling pathway activity during cardiogenesis.
