title: Characterization of secretory leukocyte protease inhibitor as an inhibitor of implantation serine proteinases.
abstract: We have recently identified and characterized two implantation serine proteinase genes, ISP1 and ISP2, which give rise to a dimeric proteinase, ISP that facilitates embryo invasion during peri-implantation period. As many proteinases have cognate serpins that regulate their proteolytic activity, we have been investigating anti-tryptases, expressed during this window of implantation. Here, we report the differential expression of secretory leukocyte protease inhibitor (SLPI) in uterine endometrium around the implantation period. The co-localization of SLPI and ISP suggests the possibility that SLPI is an ISP serpin and that expression of SLPI may lead to a reduction in ISP activity. The expression of SLPI is down regulated during the window of embryo-uterine receptivity. Our results are consistent with a model suggesting that the drop in SLPI expression may help to refine the opening of the window of implantation, by allowing the proteolytic activity of embryo invasive serine proteinases such as the ISPs.
authors.affiliation: Department of Biochemistry and Molecular Biology, Faculty of Medicine, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Navneet
authors.initials: N
authors.lastname: Sharma
authors.forename: Jaspreet
authors.initials: J
authors.lastname: Kaur
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
authors.forename: Nicole
authors.initials: N
authors.lastname: Zur Nieden
authors.forename: Derrick
authors.initials: D
authors.lastname: Rancourt
mesh_terms: D000818:Animals; D017931:DNA Primers; D010064:Embryo Implantation / Q000187:drug effects*; D005260:Female; D008565:Membrane Proteins / Q000235:genetics; D051379:Mice; D008815:Mice, Inbred Strains; D011247:Pregnancy; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053481:Secretory Leukocyte Peptidase Inhibitor / Q000494:pharmacology*; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism*; D015842:Serine Proteinase Inhibitors / Q000494:pharmacology*; D014599:Uterus / Q000187:drug effects / Q000502:physiology; D033921:Vesicular Transport Proteins
chemical_list: D017931:DNA Primers; D008565:Membrane Proteins; D053481:Secretory Leukocyte Peptidase Inhibitor; D015842:Serine Proteinase Inhibitors; C424133:Sytl1 protein, mouse; D033921:Vesicular Transport Proteins; D012313:RNA; C436412:Prss28 protein, mouse; D012697:Serine Endopeptidases