Inverted formin 2 regulates intracellular trafficking, placentation, and pregnancy outcome

Area of Science:

• Reproductive biology
• Cellular and molecular biology
• Developmental biology

Background:

• Proper placentation, involving trophoblast proliferation, differentiation, and invasion, is vital for healthy pregnancy.
• Impaired placentation can lead to placental ischemia, intrauterine growth restriction, and preeclampsia.
• The precise mechanisms governing trophoblast invasion remain largely unknown.

Purpose of the Study:

• To investigate the role of Inverted formin 2 (INF2) in regulating trophoblast invasion.
• To determine the consequences of INF2 deficiency on placentation and pregnancy outcomes in a mouse model.

Main Methods:

• Utilized a model of human extravillous trophoblasts to assess the impact of INF2 reduction on invasion.
• Generated and analyzed Inverted formin 2 knockout (Inf2-/-) mice to study maternal and fetal phenotypes.

Main Results:

• Reduced INF2 significantly impaired trophoblast invasion by altering intracellular trafficking.
• Inf2-/- dams exhibited reduced spiral artery numbers and gestational hypertension.
• Inf2-/- fetuses showed growth restriction and signs of fetal distress, with altered umbilical artery Doppler findings.
• Loss of INF2 led to increased placental vascular density and dysregulated expression of angiogenic factors.

Conclusions:

• Inverted formin 2 (INF2) plays a critical regulatory role in trophoblast invasion, a key process for successful placentation.
• INF2 deficiency recapitulates phenotypes of placental insufficiency, highlighting its importance in pregnancy.
• INF2 represents a potential therapeutic target for improving placentation and fetal outcomes in pregnancy complications.