Ds. Bischoff et Jm. Slavicek, IDENTIFICATION AND CHARACTERIZATION OF A PROTEIN-KINASE GENE IN THE LYMANTRIA-DISPAR MULTINUCLEOCAPSID NUCLEAR POLYHEDROSIS-VIRUS, Journal of virology, 68(3), 1994, pp. 1728-1736
The Lymantria dispar multinucleocapsid nuclear polyhedrosis virus (LdM
NPV) gene encoding vPK has been cloned and sequenced. LdMNPV vPK shows
a 24% amino acid identity to the catalytic domains of the eucaryotic
protein kinases nPKC from rabbits, HSPKCE from humans, APLPKCB from Ap
lysia californica, and dPKC98F from Drosophila melanogaster, and homol
ogy to several other protein kinases from yeasts, mice, and bovines. T
he homology suggests that vPK is a serine/threonine protein kinase as
defined by Hanks et al. (S. K. Hanks, A. M. Quinn, and T. Hunter, Scie
nce 241:42-52, 1988). Temporal expression studies indicate that vPK is
expressed throughout the infection cycle beginning at 4 h postinfecti
on, first as a delayed-early gene and subsequently as a late gene. Seq
uence analysis and primer extension reactions confirm the presence of
distinct early and late transcription initiation regions. Expression o
f vPK with a rabbit reticulocyte system generated a 31-kDa protein, wh
ich is in close agreement with the predicted size of 32 kDa from the a
mino acid sequence. Phosphorylation activity of in vitro-expressed vPK
was demonstrated by using calf thymus histones.