Molecular analysis of the trans-activating IE-2 gene of Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus

• Published in: Virology (New York, N.Y.) Vol. 187; no. 1; pp. 84 - 96
• Main Authors: Theilmann, David A., Stewart, Sandra
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 01.03.1992; Elsevier
• Subjects: Amino Acid Sequence; Animals; ARN; BACULOVIRIDAE; Baculoviridae - genetics; baculovirus; Base Sequence; Biological and medical sciences; Blotting, Northern; Blotting, Southern; Cell Line; CLONE; CLONES; Cloning, Molecular; Fundamental and applied biological sciences. Psychology; GENE; gene expression; GENES; Genes, Regulator; Genes. Genome; IE-2 gene; Immediate-Early Proteins; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; nuclear polyhedrosis virus; NUCLEOTIDE; nucleotide sequence; NUCLEOTIDOS; ORGYIA PSEUDOTSUGATA; Plasmids - genetics; prediction; Promoter Regions, Genetic - genetics; promoters; PROTEINAS; PROTEINE; Sequence Alignment; Sequence Homology, Nucleic Acid; Trans-Activators - genetics; Transcriptional Activation; Viral Proteins - genetics; VIRUS; Lymantriidae; Nucleotide sequence; Transcription; Transcription promoter; Insecta; Regulator gene; Gene organization; Baculovirus; Nuclear polyhedrosis virus; Virus; Baculoviridae; Arthropoda; Lepidoptera; Orgyia pseudotsugata; Invertebrata; Aminoacid sequence
• ISSN: 0042-6822; 1096-0341
• DOI: 10.1016/0042-6822(92)90297-3

A second immediate early (IE) regulatory gene of the baculovirus Orgyia pseudotsugata multicapsid nuclear polyhedrosis virus (OpMNPV) has been identified. The IE-2 gene which is homologous to the IE-N gene of Autographa californica MNPV was mapped to the HindIII A fragment of OpMNPV between 0.41 to 1.37 map units. The IE-2 gene codes for a predicted protein of 45,640 Da and analysis of the amino acid sequence shows that the protein has a highly basic amino terminal domain and a cysteine-rich domain that is similar to a zinc finger motif that is also found in the baculovirus proteins GC30 and PE-38. The I E-2 gene is expressed as a 1.3-kb transcript that was detectable by 0.5 hr postinfection (hr p.i.), reached maximum steady state levels by 6 hr p.i., and declined slightly by 48 hr p.i. Cis-acting 5′ regulatory sequences were analyzed by deletion analysis of the IE-2 promoter linked to the reporter gene chloramphenicol acetyl transferase. Maximum expression was obtained when the IE-2 promoter contained sequences 275 by upstream from the transcriptional start site, trans-Activation analysis revealed that IE-2 trans-activated the IE-1 promoter and in addition appeared to be autoregulatory.