title: Expression Cloning of Recombinant Escherichia coli lacZ Genes Encoding Cytoplasmic and Nuclear β-galactosidase Variants.
abstract: OBJECTIVE
  Nonviral vector can be an attractive alternative to gene delivery in experimental study. In spite of some advantages in comparison with the viral vectors, there are still some limitations for efficiency of gene delivery in nonviral vectors. To determine the effective expression, the recombinant Escherichia coli lacZ genes were cloned into the different variants of pcDNA3.1 and then the mammalian cells were transfected.
  
  
  METHODS
  The coding sequences of cytoplasmic and nuclear variants of lacZ gene were inserted downstream of the human cytomegalovirus immediate-early gene promoter of plasmid pcDNA3.1/myc-His C. The new cytoplasmic and nuclear constricts of E. coli β-galactosidase-coding sequences were introduced into HeLa cells with the aid of linear polyethylenimine and at 2 days post-transfection the cells were stained using 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (X-gal).
  
  
  RESULTS
  Restriction enzyme analyses revealed the proper insertion of E. coli β-galactosidase-coding sequences into the multiple cloning site of pcDNA3.1/myc-His C. The functionality of the resulting constructs designated pcDNA3.1-cyt.lacZ and pcDNA3.1-nls.lacZ(+) was confirmed by X-gal staining of HeLa cells transfected with these recombinant plasmids. While pcDNA3.1-cyt.lacZ directed the synthesis of cytoplasmically located β-galactosidase molecules, the β-galactosidase protein encoded by pcDNA3.1-nls.lacZ(+) was predominantly detected in the cell nucleus.
  
  
  CONCLUSIONS
  The expression of cytoplasmic and nuclear variant of LacZ gene confirmed the ability of pcDNA3.1 as versatility nonviral vector for the experimental gene delivery study in mammalian cells.
authors.affiliation: Anatomical Sciences Research Center, Kashan University of Medical Sciences, Kashan, Iran.
authors.forename: Homayoun
authors.initials: H
authors.lastname: Naderian
authors.forename: Zahra
authors.initials: Z
authors.lastname: Rezvani
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Atlasi
authors.forename: Hossein
authors.initials: H
authors.lastname: Nikzad
authors.forename: Af de Vries
authors.initials: Ade V
authors.lastname: Antoine
keywords: Expression cloning; HeLa cells; Polyethylenimine; Transfection; lacZ gene; pcDNA3.1/myc-His C