[Cloning and expression of pokeweed antiviral protein-II gene from the summer leaves of Phytolacca amercana]

Sheng Wu Gong Cheng Xue Bao. 2006 Jul;22(4):592-7.
[Article in Chinese]

Abstract

The cDNA sequence encoding pokeweed antiviral protein-II was cloned from the fresh summer leaves of phytolacca amercana by RT-PCR. The recombinant PAP-II was subcloned into the expression vector pET-28a(+) and expressed in E. coli BL21 after IPTG induction. SDS-PAGE analysis showed that the expressed PAP-II existed in the form of inclusion bodies. The purified fusion protein was obtained after a series of steps including cell break, inclusion body solubilization, protein refolding and purification through BBST NTA resin column. The non-radioactive ELISA-based HIV-1 integrase assay showed that the recombinant pokeweed antiviral protein-II and RTA were able to inhibit HIV-1 integrase to some extent (IC50 = 303 microg/mL, 220 microg/mL respectively). MTT assay showed that cytotoxicity of pokeweed antiviral protein II for HEP-G2 cells and Hela cells was in a dose-dependent manner with IC50 s of 93 microg/mL and 102 microg/mL, respectively. The results suggested that pokeweed antiviral protein-II is a potent anti-tumor candidate. The finding of integrase inhibitory activity and the discovery of cytotoxicity provide more insights into the anti-HIV and the anti-tumor activities of PAP-II.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cloning, Molecular
  • HIV Integrase / drug effects
  • HeLa Cells
  • Humans
  • Phytolacca americana / genetics*
  • Plant Leaves / genetics
  • Plasmids
  • Recombinant Proteins / biosynthesis*
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / pharmacology
  • Ribosome Inactivating Proteins, Type 1 / genetics*
  • Ribosome Inactivating Proteins, Type 1 / isolation & purification
  • Ribosome Inactivating Proteins, Type 1 / pharmacology

Substances

  • Recombinant Proteins
  • Ribosome Inactivating Proteins, Type 1
  • HIV Integrase
  • pokeweed antiviral protein
  • p31 integrase protein, Human immunodeficiency virus 1