Retroviral splicing suppressor requires three nonconsensus uridines in a 5' splice site-like sequence.
Rous sarcoma virus RNA contains a negative regulator of splicing (NRS) element that aids in maintenance of unspliced RNA. The NRS binds U1 snRNA at a sequence that deviates from the 5' splice site consensus by substitution of U's for A's at three positions: -2, +3, and +4. All three of these U's are important for NRS-mediated splicing suppression. Substitution of a single nonconsensus C or G at any of these sites diminished NRS activity, whereas substitution of a single A generated a preferred 5' splice site within the NRS.
Paca
R E
RE
Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA.
Hibbert
C S
CS
O'Sullivan
C T
CT
Beemon
K L
KL
D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics*; D012326:RNA Splicing; D012367:RNA, Viral / Q000235:genetics*
D012367:RNA, Viral