We have identified and sequenced a region of the Autographa californica nuclear polyhedrosis virus (AcMNPV) genome encoding the major polyhedron-derived virus structural glycoprotein gp41. The open reading frame is located entirely within the AcMNPV SstII-M fragment. The protein sequence does not have hydrophobic regions characteristic of integral membrane proteins and contains a putative O-linked GlcNAc glycosylation site. gp41 is expressed as a late gene, with transcripts starting within two consensus late transcription start sites (TAAG) located immediately upstream of the first methionine codon. A major transcription termination signal is bypassed, possibly generating a bicistronic message. Finally, the nucleotide and protein sequences of AcMNPV and Bombyx mori nuclear polyhedrosis virus are highly conserved.