PlexinD1 and semaphorin signaling are required in endothelial cells for cardiovascular development

Area of Science:

• Cardiovascular Biology
• Developmental Biology
• Neuroscience

Background:

• Congenital heart disease (CHD) is a leading cause of infant mortality worldwide.
• Semaphorin-plexin signaling is well-established for neural development, particularly axon guidance.
• Understanding novel pathways in cardiac morphogenesis is key to addressing CHD.

Purpose of the Study:

• To identify novel signaling pathways involved in cardiac morphogenesis.
• To investigate the role of semaphorin-plexin signaling in endothelial cells during heart development.
• To elucidate the cellular basis of CHD caused by PlexinD1 dysfunction.

Main Methods:

• Utilized mouse models with targeted gene inactivation.
• Examined cardiac and vascular development through histological analysis.
• Investigated cell-autonomous endothelial defects.

Main Results:

• Disruption of the class 3 semaphorin, neuropilin, and PlexinD1 pathway in mice leads to CHD and vascular patterning defects.
• Demonstrated that PlexinD1 functions in endothelial cells is critical for cardiac development.
• Showed that cell-autonomous endothelial defects, not solely neural crest abnormalities, can cause specific forms of CHD.

Conclusions:

• The semaphorin-plexin signaling pathway, including PlexinD1 in endothelial cells, plays a critical role in cardiac morphogenesis.
• Molecular mechanisms governing axon guidance in the central nervous system are conserved and function in endothelial cells for heart development.
• This finding offers new insights into the etiology of congenital heart disease and potential therapeutic targets.