M. Toisterachituv et O. Faktor, TRANSCRIPTIONAL ANALYSIS AND PROMOTER ACTIVITY OF THE SPODOPTERA-LITTORALIS MULTICAPSID NUCLEOPOLYHEDROVIRUS ECDYSTEROID UDP-GLUCOSYLTRANSFERASE GENE, Journal of General Virology, 78, 1997, pp. 487-491
The ecdysteroid UDP-glucosyltransferase gene (egt) of Spodoptera litto
ralis multicapsid nucleopolyhedrovirus (SpliMNPV) is a homologue of th
e Autographa californica MNPV (AcMNPV) egt gene, which has been found
to block insect moulting. Infection of larvae with an egt-deleted AcMN
PV resulted in enhanced mortality as compared to infection with the wi
ld-type virus. Consequently, deletion of an egt gene has been proposed
as a tempting approach for enhancing the insecticidal properties of b
aculoviruses. In a previous report we described the mapping and sequen
cing of the SpliMNPV egt gene. Here we use time-course Northern blot a
nd biochemical analyses to show the production of egt transcripts and
protein. The SpliMNPV egt transcription start sites were mapped to 22
and 25 nucleotides downstream of the TATA box by primer extension. Tra
nsient expression assays of chimeric egt promoter-chloramphenicol acet
yltransferase (cat) reporter gene constructs revealed low promoter act
ivity that was transactivated by AcMNPV immediate-early viral protein
IE-1.