The proximal promoter and the start site cooperate to specify correct U1 snRNA transcription initiation by RNA polymerase II.
AUTOR(ES)
Lescure, A
RESUMO
In this work, we attempted to gain insight into the detailed mechanism allowing correct transcription initiation of U1 snRNA genes by RNA polymerase II. Abolition of the CA motif residing at -1/+1 in the Xenopus U1 gene leads to a loss of the ability of the promoter to direct accurate initiation. A discrete site is selected only if a purine preceded by a pyrimidine is positioned at 58/57 bp downstream of the center of the PSE. The PSE alone is unable to designate a discrete initiation site. Rather, it serves to set the location of an initiation window without discriminating suitable from unsuitable initiation sites. The latter role is devoted to a PyPu sequence positioned at -1/+1. Therefore, it is the concomitant action of the PSE and an essential PyPu positioned at the proper distance from this promoter that specifies correct U1 snRNA transcription initiation by RNA polymerase II.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=312240Documentos Relacionados
- A novel approach to describe a U1 snRNA binding site
- The human U1 snRNA promoter and enhancer do not direct synthesis of messenger RNA.
- Common and unique transcription factor requirements of human U1 and U6 snRNA genes.
- U1 snRNA is cleaved by RNase III and processed through an Sm site-dependent pathway.
- A U1 snRNA binding site improves the efficiency of in vitro pre-mRNA splicing.