title: Distinct expression and localization of serine protease HtrA1 in human endometrium and first-trimester placenta.
abstract: Mammalian embryos cannot survive without the placenta. Development of the human placenta requires trophoblast proliferation, differentiation, and invasion as well as highly coordinated modulation of the maternal uterus. HtrA1 is a member of the recently identified mammalian HtrA (high temperature requirement factor A) serine protease family with a high level of expression in the placenta. In this study, we examined whether HtrA1 expression (mRNA and protein) is associated with placental development in the human. HtrA1 is up-regulated in both endometrial glands and decidual cells during endometrial preparation for embryo implantation and during first-trimester pregnancy at placentation. HtrA1 expression was also detected in certain trophoblast subtypes during early pregnancy. The villous syncytiotrophoblast and cytotrophoblast showed the strongest expression while the interstitial extravillous trophoblast showed the lowest or no expression of HtrA1. The distinct distribution of HtrA1 at the maternal-trophoblast interface suggests that HtrA1 may play a role in placental development.
authors.affiliation: Prince Henry's Institute of Medical Research, Clayton, Victoria, Australia. guiying.nie@princehenrys.org
authors.forename: Guiying
authors.initials: G
authors.lastname: Nie
authors.forename: Kathryn
authors.initials: K
authors.lastname: Hale
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Ursula
authors.initials: U
authors.lastname: Manuelpillai
authors.forename: Euan M
authors.initials: EM
authors.lastname: Wallace
authors.forename: Lois A
authors.initials: LA
authors.lastname: Salamonsen
mesh_terms: D003656:Decidua / Q000201:enzymology / Q000254:growth & development; D010064:Embryo Implantation / Q000235:genetics / Q000502:physiology; D004717:Endometrium / Q000201:enzymology*; D005260:Female; D000074289:High-Temperature Requirement A Serine Peptidase 1; D006801:Humans; D007150:Immunohistochemistry; D008597:Menstrual Cycle / Q000378:metabolism; D010920:Placenta / Q000201:enzymology*; D010929:Placentation; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012697:Serine Endopeptidases / Q000235:genetics* / Q000378:metabolism*
chemical_list: D012333:RNA, Messenger; D000074289:High-Temperature Requirement A Serine Peptidase 1; C474012:HTRA1 protein, human; D012697:Serine Endopeptidases