HAND1 knockdown disrupts trophoblast global gene expression

Area of Science:

• Developmental Biology
• Genetics
• Reproductive Biology

Background:

• Congenital heart disease (CHD) affects nearly 1% of newborns annually.
• Pregnancies with CHD are at higher risk for placental abnormalities.
• Previous studies linked Hand1 gene disruption to developmental issues in mouse models.

Purpose of the Study:

• To investigate the mechanistic effects of HAND1 gene disruption on human placenta trophoblast and vascular endothelial cell gene expression.
• To build upon prior research implicating Hand1 in CHD and placental development.

Main Methods:

• HAND1 gene expression was silenced using siRNA in BeWo cells (human trophoblast model) and human placental microvascular endothelial cells (HPMVECs).
• RNA sequencing was performed after 96 hours of HAND1 knockdown.
• Differential gene expression analysis, pathway overrepresentation, and protein association network analyses were conducted.

Main Results:

• HAND1 knockdown in BeWo cells led to significant downregulation of 664 genes and upregulation of 59 genes.
• Disrupted pathways in trophoblast cells included cell differentiation and localization.
• HAND1 knockdown had minimal impact on gene expression in HPMVECs, with only seven genes altered.

Conclusions:

• HAND1 disruption significantly alters gene expression in human trophoblast cells, impacting key developmental pathways.
• The effect of HAND1 disruption is specific to trophoblast cells, not placental vascular endothelial cells.
• Future research on genetic causes of CHD should consider the role of extra-embryonic tissues like the placenta.