Transduction of artificial transcriptional regulatory proteins into human cells

Nucleic Acids Res. 2008 Sep;36(16):e103. doi: 10.1093/nar/gkn398. Epub 2008 Jul 21.


Protein transduction (PT) is a method for delivering proteins into mammalian cells. PT is accomplished by linking a small peptide tag--called a PT domain (PTD)--to a protein of interest, which generates a functional fusion protein that can penetrate efficiently into mammalian cells. In order to study the functions of a transcription factor (TF) of interest, expression plasmids that encode the TF often are transfected into mammalian cells. However, the efficiency of DNA transfection is highly variable among different cell types and is usually very low in primary cells, stem cells and tumor cells. Zinc-finger transcription factors (ZF-TFs) can be tailor-made to target almost any gene in the human genome. However, the extremely low efficiency of DNA transfection into cancer cells, both in vivo and in vitro, limits the utility of ZF-TFs. Here, we report on an artificial ZF-TF that has been fused to a well-characterized PTD from the human immunodeficiency virus-1 (HIV-1) transcriptional activator protein, Tat. This ZF-TF targeted the endogenous promoter of the human VEGF-A gene. The PTD-attached ZF-TF was delivered efficiently into human cells in vitro. In addition, the VEGF-A-specific transcriptional repressor retarded the growth rate of tumor cells in a mouse xenograft experiment.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Line
  • Cell Line, Tumor
  • Cell Proliferation
  • Female
  • Gene Expression Regulation*
  • Humans
  • Kruppel-Like Transcription Factors / genetics
  • Kruppel-Like Transcription Factors / metabolism
  • Mice
  • Mice, Nude
  • Neoplasms / pathology
  • Neoplasms / therapy
  • Protein Transport
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Transcription Factors / chemistry
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism
  • Vascular Endothelial Growth Factor A / genetics
  • Zinc Fingers*
  • tat Gene Products, Human Immunodeficiency Virus / chemistry
  • tat Gene Products, Human Immunodeficiency Virus / genetics*


  • Kruppel-Like Transcription Factors
  • Recombinant Fusion Proteins
  • Repressor Proteins
  • Transcription Factors
  • VEGFA protein, human
  • Vascular Endothelial Growth Factor A
  • ZNF10 protein, human
  • tat Gene Products, Human Immunodeficiency Virus