Spliced HBV mRNA
More than ten spliced products of pre-genomic RNA (pgRNA) have been identified. The major 2.2kb variant transcript is spliced between the positions 2447 and 489 (Sommer et al. 2000) Rating=2, (Gunther et al. 1997) Rating=2. Its translation produces the Hepatitis B spliced protein (HBSP protein) which contains the first 47 amino acids residues of polymerase (Soussan et al. 2000) Rating=2. HBSP binds to fibrinogen gamma chain and could inhibit fibrin polymerization (Chen et al. 2010) Rating=1. Anti-HBSP antibodies are found in almost half of sera samples from chronic HBV carriers (Soussan et al. 2003) Rating=1.
The spliced pgRNA can be encapsidated and reverse transcribed giving rise to defective particles (Soussan et al. 2008) Rating=2.
Intronic splicing silencer regions: nt 3131-3163, and nt 1446-1585 (PRE-ISS) which folds into a double-hairpin structure and accounts for the lack of known spliced variants in the surrounding region.
Intronic splicing activator regions: nt 2951-2970, and nt 3051-3070