Tumor Susceptibility Gene 101 Is Required for the Maintenance of Uterine Epithelial Cells During Embryo Implantation

Abstract

Background: The tumor susceptibility gene 101 (Tsg101), a component of the endosomal sorting complex required for transport (ESCRT) complex I, is involved in multiple biological processes involving endomembranous structures and the plasma membrane. The role of Tsg101 in the uterine epithelium was investigated in Tsg101 floxed mice crossed with Lactoferrin-iCre mice (Tsg101d/d).Methods: Tsg101d/d mice were bred with stud male mice and the status of pregnancy was examined on days 4 and 6. Histological analyses were performed to examine the uterine architecture. Immunofluorescence staining of several markers was examined by confocal microscopy. Uterine epithelial cells (UECs) were isolated from Tsg101f/f and Tsg101d/d mice, and the expression of necroptosis effectors was examined by RT-PCR, western blotting, and immunofluorescence staining. UECs were also subjected to RNA expression profiling.Results: Tsg101d/d female mice were subfertile with implantation failure, showing unattached blastocysts on day 6 of pregnancy. Histological and marker analyses revealed that some Tsg101d/d day 4 pregnant uteri showed a disintegrated uterine epithelial structure. Tsg101d/d UECs began to degenerate within 18 h of culture. In UECs, expression of necroptosis effectors, such as RIPK1, RIPK3, and MLKL were first confirmed. UECs responded to a stimulus to activate necroptosis and showed increased cell death. Conclusions: Tsg101 deficiency in the uterine epithelium causes implantation failure, which accompanies epithelial defects. This study provides evidence that UECs harbor a necroptotic machinery that responds to death-inducing signals. Thus, Tsg101 expression in the uterine epithelium is required for normal pregnancy in mice.

The expression of human testis‐specific actin capping protein predicts in vitro fertilization outcomes: A novel biomarker of sperm function for assisted reproductive technology

“…26,27 And it has been reported that maternal gene expression may have a significant impact on the process of embryonic development, implantation, and pregnancy. 28,29 The expression status of hCP can be a marker for the structural and functional evaluation of sperm, but it is difficult to evaluate maternal factors, and may need to be combined with other markers to predict good blastocyst ratio and pregnancy rates. Recently, it has been reported that increased oxidative stress and inflammatory factors in patients with metabolic syndrome are a cause of implantation failure.…”