virus Research, 24 (1992) 1-19 0 1992 Elsevier Science Publishers B.V. All rights reserved 01681702/92/$05.00 VIRUS 00752 Marburg virus, a filovirus: messenger RNAs, gene order, and regulatory elements of the replication cycle * Heinz Feldmann ‘, Elke Miihlberger ‘, Anke Randolf ‘, Christiane Will ‘, Michael P. Kiley 2Ta, Anthony Sanchez 2 and Hans-Dieter Klenk ’ i zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Institut fuer Virologie, Philipps-Uniuersitaet, Marburg (F.R.G.) and 2 Special Pathogens Branch, Division of W al and Rickettsial Diseases, Centers for Infectious Diseases, Centers for Disease Control, Georgia, GA 30333 (U.S.A.) (Received 22 October 1991; revision received 12 December 1991; accepted 13 December 1991) zyxwvutsrqp Summary The genome of Marburg virus (MBG), a filovirus, is 19.1 kb in length and thus the largest one found with negative-strand RNA viruses. The gene order - 3’ untranslated region-NP-VP35-VP40-GP-VP30-VP24-L-5’ untranslated re- gion-resembles that of other non-segmented negative-strand (NNS) RNA viruses. Six species of polyadenylated subgenomic RNAs, isolated from MBG-infected cells, are complementary to the negative-strand RNA genome. They can be translated in vitro into the known structural proteins NP, GP (non-glycosylated form), VP40, VP35, VP30 and VP24. At the gene boundaries conserved transcrip- tional start (3’-NNCUNCNUNUAAUU-5’) and stop signals (3’-UAAUUCUU- UUU-5’) are located containing the highly conserved pentamer 3’-UAAUU-5’. Comparison with other NNS RNA viruses shows conservation primarily in the termination signals, whereas the start signals are more variable. The intergenic regions vary in length and nucleotide composition. All genes have relatively long 3’ and 5’ end non-coding regions. The putative 3’ and 5’ leader RNA sequences of Correspondence to: H. Feldmann, Institut fuer Virologie, Philipps-Universitaet, Robert Koch-Strasse 17, Marburg, F.R.G. a Present address: Research and Development Program, Government Service Division, Salk Institute, Swiftwater, PA 18370, U.S.A. * Presented in part at the Eighth International Conference on Negative Strand Viruses, Charleston, SC, U.S.A., 15-20 September 1991.