Dynamic changes to claudins in the uterine epithelial cells of the marsupial Sminthopsis crassicaudata (Dasyuridae) during pregnancy. Issue 6 (4th April 2019)

• Record Type: Journal Article
• Authors: Buddle, Alice L.; Thompson, Michael B.; Lindsay, Laura A.; Murphy, Christopher R.; Whittington, Camilla M.; McAllan, Bronwyn M.
• Is Part Of: Molecular reproduction and development. Volume 86:Issue 6(2019)
• Page Start: 639
• Page End: 649
• Publication Date: 2019-04-04
• Subjects: claudins -- endotheliochorial -- tight junctions -- uterine epithelium; Reproduction -- Periodicals; Molecular biology -- Periodicals; Molecular genetics -- Periodicals; Embryology -- Periodicals; 571.8
• DOI: 10.1002/mrd.23140
• Languages: English
• ISSNs: 1040-452X

Abstract

Abstract: The fluid that surrounds the embryo in the uterus contains important nourishing factors and secretions. To maintain the distinct microenvironment in the uterine lumen, the tight junctions between uterine epithelial cells are remodeled to decrease paracellular movement of molecules and solutes. Modifications to tight junctions between uterine epithelial cells is a common feature of pregnancy in eutherian mammals, regardless of placental type. Here we used immunofluorescence microscopy and western blot analysis to describe distributional changes to tight junctional proteins, claudin‐1, ‐3, ‐4, and ‐5, in the uterine epithelial cells of a marsupial species, Sminthopsis crassicaudata. Immunofluorescence microscopy revealed claudin‐1, ‐3, and ‐5 in the tight junctions of the uterine epithelium of S. crassicaudata during pregnancy. These specific claudins are associated with restricting passive movement of fluid between epithelial cells in eutherians. Hence, their function during pregnancy in S. crassicaudata may be to maintain the uterine luminal content surrounding developing embryos. Claudin‐4 disappears from all uterine regions of S. crassicaudata at the time of implantation, in contrast with the distribution of this claudin in some eutherian mammals. We conclude that like eutherian mammals, distributional changes to claudins in the uterine epithelial cells of S. crassicaudata are necessary to support pregnancy. However, the combination of individual claudin isoforms in the tight junctions of the uterine epithelium of S. crassicaudata differs from that of eutherian mammals. Our findings suggest that the precise permeability of the paracellular pathway of the uterine epithelium is species‐specific. Abstract : Successful pregnancy requires careful regulation of the fluid surrounding developing embryos in the uterus. Our findings suggest that the claudin composition of tight‐junction strands between uterine epithelial cells are modified during different stages of pregnancy in a marsupial species, the fat‐tailed dunnart, to ensure uterine luminal fluid content is maintained. This study highlights important differences in the molecular composition of tight junctions in the uterine epithelial cells of marsupial mammals and eutherian mammals, through pregnancy. Differences between species suggest that the precise permeability of the uterine epithelium may be species‐specific.