title: Expression and activation of the membrane-cytoskeleton protein ezrin during the normal endometrial cycle.
abstract: OBJECTIVE
  To examine total ezrin expression (ezrin and phospho-ezrin) through the normal endometrial cycle and to correlate ezrin activation and localization with cytologic changes.
  
  
  METHODS
  Experimental laboratory study.
  
  
  METHODS
  University medical centers.
  
  
  METHODS
  Reproductive-age women.
  
  
  METHODS
  A total of 36 samples of normal early, mid-, and late proliferative- and secretory-phase endometrium were studied for immunoreactive total ezrin (ir-T-ezrin) and phospho-ezrin (ir-p-ezrin) expression by histology, immunohistochemistry, and Western blotting.
  
  
  METHODS
  Total ezrin and phospho-ezrin expressions through the normal endometrial cycle.
  
  
  RESULTS
  Throughout the cycle ir-T-ezrin is present in the epithelium. The intensity and localization of both ir-ezrin and ir-p-ezrin vary greatly throughout the cycle. The main findings include the following: lateral localization of ir-ezrin/ir-p-ezrin in association with membrane specializations; dense staining around secretory vacuoles (secretory phase); dense staining of the apical surfaces, including microvilli and pinopodes of epithelial cells, especially during the mid- to late secretory phases; and the presence of ezrin in the glandular secretions. Immunoreactive total ezrin and ir-p-ezrin were not expressed by stromal fibroblasts.
  
  
  CONCLUSIONS
  Ezrin is a prominent protein in the cycling endometrium. The most striking findings were the gravitation of ir-ezrin/ir-p-ezrin to the periphery of secretory vacuoles, localization on apical surfaces of the luminal epithelium, dense ezrin staining in secretory-phase epithelial cell plumes, and the presence of ir-ezrin/ir-p-ezrin in secretory-phase luminal secretions. These findings may have functional implications, especially for implantation biology.
authors.affiliation: Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, Texas, USA.
authors.forename: Orkun
authors.initials: O
authors.lastname: Tan
authors.forename: Turkan
authors.initials: T
authors.lastname: Ornek
authors.forename: Ahmed
authors.initials: A
authors.lastname: Fadiel
authors.forename: Kelley S
authors.initials: KS
authors.lastname: Carrick
authors.forename: Aydin
authors.initials: A
authors.lastname: Arici
authors.forename: Kevin
authors.initials: K
authors.lastname: Doody
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Carr
authors.forename: Frederick
authors.initials: F
authors.lastname: Naftolin
mesh_terms: D000328:Adult; D003598:Cytoskeletal Proteins / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D010064:Embryo Implantation / Q000502:physiology; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005347:Fibroblasts / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000378:metabolism; D008597:Menstrual Cycle / Q000378:metabolism*; D008875:Middle Aged; D010766:Phosphorylation / Q000502:physiology; D011247:Pregnancy; D022142:Secretory Vesicles / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism*; D014617:Vacuoles / Q000378:metabolism; D055815:Young Adult; D000099149:Ezrin
chemical_list: D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D000099149:Ezrin