Journal of General Virology, Vol 80, 117-123, Copyright © 1999 by Society for General Microbiology
RNA editing-like phenomenon in paramyxovirus V gene mRNA observed in insect cells infected with a recombinant baculovirus
H Matsumura, N Ikemura, Y Ito and K Kuribayashi
Department of Immunology, Kinki University School of Medicine, Osaka- Sayama, Osaka, Japan. matumura@med.kindai.ac.jp
The V gene of the paramyxovirus human parainfluenza virus type 2 (hPIV2) is
transcribed into both V and P mRNA. The V mRNA is a faithful transcript of
the V gene; however, the P mRNA is transcribed by an RNA- editing mechanism
in hPIV2-infected mammalian cells. Recombinant baculoviruses (rBV) were
constructed containing the wild-type V gene, which has seven G residues at
its editing site, and a manipulated V gene with ten G residues at its
editing site. A small amount of the P protein was synthesized, in addition
to the V protein, when the wild- type V gene was expressed in rBV-infected
insect cells. Furthermore, synthesis of the P protein increased when rBV
containing the manipulated V gene was used to infect insect cells. Both the
P and V proteins were detected after in vitro translation of mRNA from rBV-
infected cells. Moreover, G-residue insertions and a deletion were detected
in mRNA. Since the P protein was not detected after in vitro translation of
V RNA that had been transcribed in vitro by T7 RNA polymerase, these
results suggest that the non-encoded G residues were inserted and deleted
during transcription in insect cells. This RNA editing-like phenomenon and
the implications of the length of the G cluster are discussed.
