title: Inhibitory G protein alpha subunit (Gi alpha) expression and localization during human trophoblast differentiation.
abstract: OBJECTIVE
  Cyclic adenosine monophosphate (cAMP) participates in the regulation of processes associated with trophoblast syncytialization. As guanosine triphosphate (GTP)-binding regulatory proteins (G-proteins) modulate adenylate cyclase activity, the present study investigated the expression and regulation of the alpha subunit of inhibitory G protein (Gi alpha) during human trophoblast differentiation in vitro.
  
  
  METHODS
  Protein levels and the immunolocalization of the protein at a subcellular-level were assessed.
  
  
  RESULTS
  Expression of Gi alpha protein decreased during syncytialization. Moreover, Gi alpha transmigrated from a predominantly cell membrane-associated to a predominantly perinuclear location during the process.
  
  
  CONCLUSIONS
  These results suggest that Gi alpha is regulated and may be implicated in cAMP-dependent events during the terminal differentiation of human trophoblasts.
authors.affiliation: Department of Obstetrics and Gynecology and Center for Research in Women's Health and Reproduction, University of Pennsylvania Medical Center, Philadelphia 19104, USA.
authors.forename: E
authors.initials: E
authors.lastname: Daiter
authors.forename: A
authors.initials: A
authors.lastname: Makrigiannakis
authors.forename: G
authors.initials: G
authors.lastname: Coukos
authors.forename: M J
authors.initials: MJ
authors.lastname: Woolkalis
authors.forename: C
authors.initials: C
authors.lastname: Coutifaris
mesh_terms: D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D001345:Autoradiography; D002454:Cell Differentiation; D002462:Cell Membrane / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism; D046508:Culture Techniques; D019084:Fluorescent Antibody Technique, Indirect; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000032:analysis* / Q000378:metabolism*; D006801:Humans; D009243:NAD / Q000378:metabolism; D013997:Time Factors; D014327:Trophoblasts / Q000737:chemistry / Q000502:physiology*
chemical_list: D009243:NAD; D000246:Adenosine Diphosphate Ribose; D019206:GTP-Binding Protein alpha Subunits, Gi-Go