Glycomics reveal that ST6GAL1‐mediated sialylation regulates uterine lumen closure during implantation

Abstract

Objectives Implantation failure is a major cause of prenatal mortality. The uterine lumen closure contributes to embryo adhesion to the uterus, but its underlying mechanisms are largely unknown. Our previous study has reported that endometrial fold extension can lead to uterine lumen closure in pigs. The objective of this study was to reveal molecular mechanisms of the uterine lumen closure by characterizing the molecular basis of the endometrial fold extension during implantation in pigs. Materials and methods Uterine and endometrium tissues during implantation were collected in pigs. MALDI‐TOF MS was used to characterize the N‐glycomic profiles. Histochemistry, siRNA transfection, Western blotting, lectin immumoprecipitation, mass spectrometry and assays of wounding healing and cell aggregation were performed to investigate the molecular basis. Results We observed that uterine luminal epithelium (LE) migrated collectively during endometrial fold extension. For the first time, we identified a large number of N‐glycan compositions from endometrium during implantation using MALDI‐TOF MS. Notably, the α2,6‐linked sialic acid and ST6GAL1 were highly expressed in uterine LE when the endometrial folds extended greatly. Subsequently, the role of ST6GAL1‐mediated 2,6‐sialylation in collective epithelial migration was demonstrated. Finally, we found that ST6GAL1‐mediated α2,6‐sialylation of E‐cadherin may participate in collective migration of uterine LE. Conclusions The study reveals a mechanism of uterine lumen closure by identifying that ST6GAL1‐mediated α2,6‐sialylation of cell adhesion molecules contributes to endometrial fold extension through regulating collective migration of uterine LE.

Genetic basis of phenotypic convergence in pig terminal sires using pathway‐based selection signature detection methods

“…Among them, the RAB14 gene was highly expressed in adipose tissue (Liu et al., 2008) and the PLIN5 gene was related to fat metabolism (Zhou et al., 2012). Additionally, the ST6GAL1 gene can affect the reproduction process by regulating the closure of the neutron cavity during implantation (Han et al., 2022). There were also other important candidate genes such as PLAG1 and TNNI3 related to growth and meat quality traits (Qiao et al., 2015; Yang et al., 2011) (Table S4).…”