title: Identification of a unique splicing regulatory cluster in hepatitis B virus pregenomic RNA.
abstract: HBV particles with genome derived from spliced mRNAs accumulate in patients with virus-derived severe liver necrosis and fibrosis. We investigated the role of an intronic element (intronic splicing silencer-long, ISS(L)) on splicing of HBV minigene transcripts. Removal of the entire ISS(L) showed two-fold increase in splicing while shorter deletions within ISS(L) indicated isolated clusters of activator and repressor domains. Activator domains stimulated splicing in presence of PRE, a long HBV 3' exon and even when present in a heterologous context. Mutations in the repressor domain unexpectedly augmented repression. The role of this intronic splicing regulatory element could be important for HBV pathogenesis.
authors.affiliation: Department of Microbiology, University of Calcutta, University College of Science and Technology, Kolkata, India.
authors.forename: Joydip Bhanja
authors.initials: JB
authors.lastname: Chowdhury
authors.forename: Dipika
authors.initials: D
authors.lastname: Roy
authors.forename: Sagarmoy
authors.initials: S
authors.lastname: Ghosh
mesh_terms: D002460:Cell Line; D005091:Exons / Q000502:physiology*; D016679:Genome, Viral / Q000502:physiology*; D006515:Hepatitis B virus / Q000502:physiology*; D006801:Humans; D007438:Introns / Q000502:physiology*; D009154:Mutation; D012326:RNA Splicing / Q000502:physiology*; D012367:RNA, Viral / Q000235:genetics / Q000378:metabolism*
chemical_list: D012367:RNA, Viral