title: Complex patterns of ADAM12 mRNA and protein splice variants in the human placenta.
abstract: OBJECTIVE
  Trophoblast fusion in the placenta is prerequisite to successful pregnancy and the pathological conditions related to it. The presence of syncytin-1, is not sufficient to explain the complete event and ADAM12 is a major co-player candidate. Via differential splicing, the ADAM12 gene produces a short and a long form, being the ADAM12-S and the ADAM12-L respectively.
  
  
  RESULTS
  We investigated the localisation of both variants in the human placenta using whole mount in situ hybridisation, immunohistochemistry and Northern blotting in 1st (n=8) and 3rd (n=8) trimester placentae and in the case of NB in several cell lines. In Northern blotting, 1st and 3rd trimester placentae were positive for the ADAM12-S and Bewo, 293HEK, JAR, leucocytes, macrophages, 1st and 3rd trimester placentae were positive for ADAM12-L. In whole mount in situ hybridisation, the 1st and 3rd trimester placental syncytium was positive for both variants. In immunohistochemistry, ADAM12-L localised in the cytotrophoblast of both 1st and 3rd trimester placentae, while ADAM12-S localised in the complete syncytium, often including the cytotrophoblast.
  
  
  CONCLUSIONS
  The different localisation of ADAM12-S and ADAM12-L indicates a possible different role making ADAM12-L a candidate for the fusion event, while the syncytial localisation of the ADAM12-S makes it a candidate for cell-cell and cell-matrix interactions between the placental syncytium and the maternal interface.
authors.affiliation: Institute of Anatomy and Cell Biology, Faculty of Medicine, RWTH Aachen University, Aachen, Germany. mkokozidou@ukaachen.de
authors.forename: M
authors.initials: M
authors.lastname: Kokozidou
authors.forename: S
authors.initials: S
authors.lastname: Drewlo
authors.forename: C
authors.initials: C
authors.lastname: Bartz
authors.forename: G
authors.initials: G
authors.lastname: Raven
authors.forename: L O
authors.initials: LO
authors.lastname: Brandenburg
authors.forename: C J
authors.initials: CJ
authors.lastname: Wruck
authors.forename: T
authors.initials: T
authors.lastname: Pufe
mesh_terms: D051722:ADAM Proteins / Q000235:genetics*; D000072199:ADAM12 Protein; D005260:Female; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D010920:Placenta / Q000502:physiology*; D011247:Pregnancy; D020033:Protein Isoforms / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics*; D014018:Tissue Distribution
chemical_list: D008565:Membrane Proteins; D020033:Protein Isoforms; D012333:RNA, Messenger; D051722:ADAM Proteins; D000072199:ADAM12 Protein; C000606480:ADAM12 protein, human