title: Functional expression of the human coagulation factor IX using heterologous signal peptide and propeptide sequences in mammalian cell line.
abstract: OBJECTIVE
  To study the functions of pre-pro leader peptides of the human and porcine prothrombins on the human FIX (hFIX) expression.
  
  
  RESULTS
  In silico analysis predicted higher secretion efficiencies for the prothrombins-derived signal peptides, in comparison with the native hFIX signal peptide. Replacements of the hFIX pre-pro sequence with those of the two prothrombins, led to increased levels of transcription of the chimeric transgenes, as compared to the native clone. This was in consistent with the lower minimum free energies, calculated for the recombinant transcripts, based on their secondary structures. Evaluation of secretion efficiency revealed that the highest and lowest FIX secretions belong to signal peptides derived from porcine' prothrombin and hFIX, respectively. Coagulation activities of the FIX expressed from chimeric variants could be increased up to tenfold, relative to the native clone.
  
  
  CONCLUSIONS
  The feasibility of a leader-peptide replacement for the improvement of both transcription and post-transcriptional processes is described that can be relevant for production the vitamin-K dependent proteins.
authors.affiliation: Department of Molecular Genetics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Shohreh
authors.initials: S
authors.lastname: Khorshidi
authors.forename: Alireza
authors.initials: A
authors.lastname: Zomorodipour
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Behmanesh
authors.forename: Jafar
authors.initials: J
authors.lastname: Vatandoost
authors.forename: Mettine H A
authors.initials: MH
authors.lastname: Bos
mesh_terms: D000818:Animals; D003198:Computer Simulation; D005164:Factor IX / Q000235:genetics / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D021382:Protein Sorting Signals / Q000235:genetics*; D011516:Prothrombin / Q000235:genetics* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism*; D013552:Swine / Q000235:genetics / Q000378:metabolism
chemical_list: D021382:Protein Sorting Signals; D011994:Recombinant Proteins; D011516:Prothrombin; D005164:Factor IX