Fig. 4: The protein factors are dispensable for alternative splicing from specific 5’SS variants.
From: Mechanism of alternative splicing of yeast HEH1 through competing 5’ splice sites
a Pairing of U5 and U6 snRNAs to HEH1 WT pre-mRNA and its variants #7 HEH1S•{A(+4)U} or HEH1L•{A( − 1)U}; #15 {HEH1S•{G(+7)A,A(+8)U,G(+9)A} or HEH1L•{G(+3)A,A(+4)U,G(+5)A}; and #18 HEH1S•{C(+2)U,A(+4)U,G(+7)A,A(+8)U} or HEH1L•{C(−3)U,A(−1)U,G(+3)A,A(+4)U}. Nucleotide changes are underlined. Upward/downward arrows refer to an increase/decrease in U5/U6 pairing strengths to HEH1 isoforms, and double upward arrows represent the yeast canonical 5’SS (GUAUGU or GUAAGU). b Alternative splicing of HEH1 variants #7, 15, and 18 was analyzed in the mutant strains by western blot. Partial rescue of Heh1S in the prp8-101 strain is shown in the dotted box. Data shown as mean ± s.d. (n = 3 independent repeats). c ACT1–CUP1 reporter with a single 5’SS was used to understand the exclusive production of Heh1S from #7 {A(+4)U}. U5 and U6 snRNAs pairing to HEH1S 5’SS GCAAGU, GCAUGU, and GUAUGU were compared by growth at indicated CuSO4 concentrations (in mM), which correlates with their splicing efficiency. The underlined nucleotides show changes compared to the HEH1S 5’SS GCAAGU.
