Functional analysis of promoter element 2 within the viral polymerase gene of an emerging paramyxovirus, Sosuga virus

• Published in: Microbiology spectrum Vol. 13; no. 5; p. e0053425
• Main Authors: Akter, Lipi, Kawasaki, Junna, Rakib, Tofazzal Md, Okura, Takashi, Kato, Fumihiro, Kojima, Shohei, Oda, Kosuke, Matsumoto, Yusuke
• Format: Journal Article
• Language: English
• Published: United States American Society for Microbiology 10.04.2025
• Subjects: negative-strand RNA virus; paramyxovirus; promoters; Research Article; RNA polymerases; viral replication; Virology; viral replication; promoters; RNA polymerases; negative-strand RNA virus; paramyxovirus
• ISSN: 2165-0497; 2165-0497
• DOI: 10.1128/spectrum.00534-25

Paramyxoviruses are classified into three major subfamilies: Orthoparamyxovirinae , Avulavirinae , and Rubulavirinae . All paramyxovirus genomes and antigenomes possess bipartite promoters, comprising two elements: promoter element 1 (PE1) at the 3′ end and promoter element 2 (PE2) located internally. We previously revealed that, in many Rubulavirinae , the antigenomic PE2 lies within the coding region of the viral RNA polymerase L gene. In this study, we used Sosuga virus, a member of the Rubulavirinae subfamily, to elucidate the role of antigenomic PE2 in viral replication. Because the PE2 region encodes part of the L protein, its presence leads to a distinctive motif at the C-terminus of L protein. Notably, this motif is conserved in all Rubulavirinae , including those that do not harbor the antigenomic PE2 within their L gene, indicating its importance in viral propagation.