Expression Of Transmembrane Protein 43 In Placenta Of Patients With Preeclampsia And Its Effect On The Function Of Trophoblast Cells

Placenta is a special temporary organ in the process of mammalian pregnancy.The placenta villi,which are composed of many kinds of trophoblast cells and cells derived from endodermal mesoderm,is the basic structure and function unit of the placenta.The abnormal proliferation,differentiation and function of trophoblast cells can cause a series of pregnancy diseases,such as preeclampsia and abortion.Currently,the molecular mechanism of extravillous trophoblast cell differentiation and its maintenance of invasiveness is not clear.Previous studies found that placenta associated 8(PLAC8)was abnormally expressed in the placenta of preeclampsia,and transmembrane protein 43(TMEM43)was found to be one of the important proteins of its interaction by immunocoprecipitation.To determine whether TMEM43 is involved in the development of preeclampsia by affecting the function of trophoblast cells,the following studies were conducted: In this study,we collected human preeclampsia and normal pregnancy placentas,and compared the transcription level and protein expression level of TMEM43 by real-time quantitative PCR and Western blot.The expression and localization of TMEM43 in human maternal-fetal interface at the 6th and 21 st week of gestation were studied by immunohistochemistry.Subsequently,human immortalized trophoblast cell line HTR-8/SVneo was used to construct trophoblast cell line which stable overexpression of TMEM43 by lentivirus infection combined with drug screening.Firstly,the effects of tmem43 overexpression on trophoblast cell proliferation and apoptosis were detected by CCK-8,edu labeling and flow cytometry.The effects of TEME43 up-regulation on trophoblast cell migration and invasion were studied by scratch healing experiment,Transwell cell migration and invasion model.Finally,the co-location and interaction between TMEM43 and nuclear membrane stability regulatory protein Emerin were detected by immunofluorescence and immunoprecipitation.The results showed that the expression of TMEM43 m RNA and protein in preeclampsia placenta was significantly lower than that in normal pregnancy placenta(p < 0.05,p < 0.01).TMEM43 was widely expressed in the maternal-fetal interface during the first and second trimester of pregnancy,but highly expressed in interstitial extravillous trophoblast cells(i EVT)and vascular extravillous trophoblast cells(e EVT).The up regulation of TMEM43 mediated by lentivirus can significantly promote the migration and invasion of trophoblast cells.Immunofluorescence showed that TMEM43 was mainly located in the position with the most severe nuclear membrane deformation in HTR-8/SVneo cells with movement trend,but evenly distributed in stable cells.Further,the co-localization and interaction between TMEM43 and Emerin in HTR-8/SVneo cell were found by immunofluorescence and immunocoprecipitation.Collectively,the results showed that the expression of TMEM43 was widely in the placenta,but low in the placenta of preeclampsia,and the up-regulation of TMEM43 promoted the migration and invasion of trophoblast cells,this regulation may be achieved by regulating the stability of the nuclear membrane,the specific mechanism needs to be further studied.