FIGURE 5.
Truncation of Prp45 opens a gap between U1 dissociation and U2/U5 snRNP recruitment. (A) Scheme of Prp45 conformation and contacts within the spliceosome. The ribbon diagram combines information from the cryo-EM structure of the S. cerevisiae Bact (5GM6) and human C* (5MQF) complexes (Yan et al. 2016; Bertram et al. 2017). Amino acids missing in the Prp45(1–169) mutant are labeled red (i.e., 170–379). Regions of close contact for Prp45 and proteins/RNA (i.e., encompassing <4 Å intermolecular distances) are indicated by gray ovals. (B) Scheme summarizing the effect of the prp45(1–169) allele on cotranscriptional splicing. The amplicons used for ChIP analysis are indicated by lines under the gene diagram.