Type V Collagen Controls Decidual Extracellular Matrix Organization and Angiogenesis During Embryo Implantation

Area of Science:

• Reproductive biology
• Extracellular matrix biology
• Developmental biology

Background:

• Endometrial decidualization involves extracellular matrix (ECM) remodeling and angiogenesis for embryo implantation.
• Fibrillar collagens are key ECM structural components undergoing reorganization during decidualization.
• The specific role of type V collagen, a regulator of collagen fibrillogenesis, in pregnancy is unknown.

Purpose of the Study:

• To investigate the functional role of type V collagen (encoded by Col5a1) in mouse uterine decidualization and pregnancy.

Main Methods:

• Utilized conditional gene deletion of Col5a1 in mice.
• Analyzed uterine structure, collagen organization, embryo implantation, and decidual angiogenesis.
• Performed transcriptomic profiling of Col5a1-deficient decidua.

Main Results:

• Col5a1 is highly expressed in decidual stromal and endothelial cells.
• Col5a1 deficiency caused progressive uterine hemorrhage, embryo resorption, and pregnancy loss.
• Absence of Col5a1 led to decidual structural distortion, collagen disorganization, impaired embryo invasion, and disrupted angiogenesis.
• Transcriptomic analysis revealed COL5A1-regulated gene expression signatures and signaling pathways.

Conclusions:

• Type V collagen is essential for maintaining decidual integrity during pregnancy.
• COL5A1 plays a critical role in supporting decidual angiogenesis and vascular network formation.
• Type V collagen is indispensable for successful embryo implantation and overall pregnancy maintenance.