A novel mechanism for Prp5 function in prespliceosome formation and proofreading the branch site sequence.

ABSTRACT: The DEAD-box RNA helicase Prp5 is required for the formation of the prespliceosome through an ATP-dependent function to remodel U2 small nuclear ribonucleoprotein particles (snRNPs) and an ATP-independent function of unknown mechanism. Prp5 has also been implicated in proofreading the branch site sequence, but the molecular mechanism has not been well characterized. Using actin precursor mRNA (pre-mRNA) carrying branch site mutations, we identified a Prp5-containing prespliceosome with Prp5 directly bound to U2 small nuclear RNA (snRNA). Prp5 is in contact with U2 in regions on and near the branchpoint-interacting stem-loop (BSL), suggesting that Prp5 may function in stabilizing the BSL. Regardless of its ATPase activity, Prp5 mutants that suppress branch site mutations associate with the

SUBMITTER: Liang WW 

PROVIDER: S-EPMC4281567 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature