Serine/threonine kinase (pk-1) is a component of Autographa californica multiple nucleopolyhedroviru
June 27th, 2008 | by admin |Serine/threonine kinase (pk-1) is a component of Autographa californica multiple nucleopolyhedrovirus (AcMNPV) very late gene transcription complex and it phosphorylates a 102kDa polypeptide of the complex.
The baculovirus gene, protein kinase-I (pk-1) encodes a serine/threonine kinase that is essential for very late gene expression. Late and very late genes of the baculoviruses are transcribed by an alpha-amanitin resistant RNA polymerase. The very late gene promoter transcription initiation complex was isolated from nuclei of Autographa californica multiple nucleopolyhedrovirus (AcMNPV)-infected Sf9 cells by DNA affinity purification and found to contain 4 major polypeptides of sizes approximately 102, 38, 32, and 18kDa. The 32kDa polypeptide was immunoreactive to AcMNPV anti-pk-1 antibody and phosphorylated the 102kDa polypeptide, earlier reported as late gene expression factor LEF-8. Electrophoretic mobility shift assays with anti-pk-1 antibody indicated the binding of promoter DNA with recombinant AcMNPV-pk-1 and transcription initiation complex proteins. All these results suggested AcMNPV-pk-1 to be a component of the viral very late gene transcription initiation complex.
Mishra G, Chadha P, Das RH.
Comparative Genomics Unit, Institute of Genomics and Integrative Biology (CSIR), Delhi University Campus, Mall Road, Delhi 110007, India.