Catalyzes pseudouridylation at position 35 in U2 snRNA stem-loop II region which induces particular conformation of the mRNA-U2 snRNA duplex and places the nucleophile in an accessible position for the first step of splicing (PubMed:12426583, PubMed:12682021, PubMed:15611063, PubMed:18435545, PubMed:19114708, PubMed:25219674). Also catalyzes pseudouridylation at position 56 in U2 snRNA (PubMed:21131909). Catalyzes also pseudouridylation at position 50 in 5S rRNA, position 13 in cytoplasmic tRNAs, and position 35 in pre-tRNA(Tyr) (PubMed:14561887, PubMed:18332121, PubMed:25219674, PubMed:35058356). Pseudouridine residues in tRNAs may stabilize the local RNA conformation, favor interactions with protein partners and play an important role in the stabilization of the codon-anticodon interaction with mRNA (PubMed:14561887). Also catalyzes pseudouridylation of mRNAs in response to heat shock: mediates pseudouridylation of mRNAs with the consensus sequence 5'-UGUAR-3' (PubMed:25219674, PubMed:35058356). uridine in 5S rRNA = pseudouridine in 5S rRNA uridine in snRNA = pseudouridine in snRNA uridine(13) in tRNA = pseudouridine(13) in tRNA a uridine in mRNA = a pseudouridine in mRNA Predominantly nuclear in 30 degrees Celsius and primarily cytoplasmic in heat shock. Decreased level of pseudouridylated mRNAs. Present with 4150 molecules/cell in log phase SD medium. Belongs to the pseudouridine synthase TruD family.