Prespliceosome structure provides insights into spliceosome assembly and regulation.

ABSTRACT: The spliceosome catalyses the excision of introns from pre-mRNA in two steps, branching and exon ligation, and is assembled from five small nuclear ribonucleoprotein particles (snRNPs; U1, U2, U4, U5, U6) and numerous non-snRNP factors¹. For branching, the intron 5' splice site and the branch point sequence are selected and brought by the U1 and U2 snRNPs into the prespliceosome¹, which is a focal point for regulation by alternative splicing factors². The U4/U6.U5 tri-snRNP subsequently joins the prespliceosome to form the complete pre-catalytic spliceosome. Recent studies have revealed the structural basis of the branching and exon-ligation reactions³, however, the structural basis of the early events in spliceosome assembly remains poorly under

SUBMITTER: Plaschka C 

PROVIDER: S-EPMC6141012 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature