Functional analysis of Hsh155/SF3b1 interactions with the U2 snRNA/branch site duplex.

ABSTRACT: SF3b1 is an essential component of the U2 snRNP implicated in branch site (BS) recognition and found to be frequently mutated in several human cancers. While recent structures of yeast and human SF3b1 have revealed its molecular architecture, the importance of specific RNA:protein contacts and conformational changes remains largely uncharacterized. Here, we performed mutational analysis of yeast SF3b1, guided by recent structures of the spliceosome. We find that conserved amino acids contacting the U2 snRNA backbone of the U2/BS duplex are nonessential, and that yeast can tolerate truncation of the HEAT repeats containing these amino acids. The pocket housing the branchpoint adenosine (BP-A) is also amenable to mutation despite strong conservation. However, mutations that support viability

SUBMITTER: Carrocci TJ 

PROVIDER: S-EPMC6049509 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature