title: Analysis of protein-protein interactions and proteomic profiles of normal human lenses.
abstract: OBJECTIVE
  To investigate proteomic profiles of normal human lenses and their key proteins in protein-protein interactions (PPIs).
  
  
  METHODS
  Water-soluble and water-insoluble proteins extracted from human lenses were first separated by one-dimensional sodium dodecyl sulfate polyacrylamide gel, and then in-gel digested with trypsin into peptides eluted by reversed-phase high-performance liquid chromatography. The eluted peptides were analyzed by linear ion trap tandem mass spectrometry (MS/MS). The raw data was filtered by TurboSEQUEST algorithm. The reverse database was used for peptide false-positive rate estimation. A network chart was constructed by the identified lens PPIs in accordance with interaction database systems.
  
  
  RESULTS
  From normal human lenses 339 proteins in total were identified, including many formerly unidentified low-abundance proteins. Key proteins we recognized included plectin, actin, spectrin (alpha, beta), vimentin, 14-3-3 protein (beta/alpha, zeta/delta, epsilon, gamma, eta), TSC2, guanine nucleotide-releasing protein, laminin gamma, mitogen-activated protein kinase, alpha-A-crystallin, heat-shock protein (alpha, beta), glyceraldehyde 3-phosphate dehydrogenase, and collagen IV alpha.
  
  
  CONCLUSIONS
  Key proteins of normal human lenses were studied by constructing a network chart of the identified lens PPIs. The results suggest that linear ion trap MS/MS is an effective tool for detecting low-abundance proteins of human lenses. This study provides valuable data for further proteomic research of the human lens development and lens diseases.
authors.affiliation: Department of Ophthalmology, Fourth Affiliated Hospital, China Medical University, Shenyang, China.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Yao
authors.forename: Hong
authors.initials: H
authors.lastname: Yu
authors.forename: Dwight
authors.initials: D
authors.lastname: Xuan
authors.forename: Qian
authors.initials: Q
authors.lastname: Sha
authors.forename: Jianwen
authors.initials: J
authors.lastname: Hu
authors.forename: Jinsong
authors.initials: J
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000465:Algorithms; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005136:Eye Proteins / Q000032:analysis*; D006801:Humans; D007908:Lens, Crystalline / Q000737:chemistry*; D008297:Male; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods*; D040901:Proteomics; D053719:Tandem Mass Spectrometry
chemical_list: D005136:Eye Proteins