Extended Data Fig. 8: Casein kinase inhibition or mutation of SF3A3 Ser365/367/369 prevents polyamine deprivation–induced alternative splicing.
From: Polyamine-dependent metabolic shielding regulates alternative splicing
a, Western blot analysis of CK1 expression in DU145 cells treated with the CK inhibitor CX4945 (10 µM, 48 h). b, c, z-scored heat map (Abs(ΔPSI) > 10 %, adj-p < 0.1) representation of all the alternative splicing events (b), and semi-quantitative PCR gels of selected AS events (c) in DU145 shAMD1 cells silenced with doxycycline (100 ng/mL, 48 h), with or without CX4945 co-treatment (10 µM, 24 h). d, e, Schematic representation of the experimental design (https://BioRender.com/1byzvwp) (d) and genotyping strategy by sequencing (e) of CRISPR-Cas9–generated mice transduced with either wild-type (WT) or mutant Sf3a3 in which the phosphosites Ser365, Ser367, and Ser369 were replaced by alanine. f, g, LC-MS metabolomics of total polyamines and [¹³C]-methionine incorporation (WT, left; KI/KI, right) (f), and z-scored heat map representation of exonic events (left) and all the alternative splicing events (right) (g) in mouse embryonic fibroblasts (MEFs) treated with or without SAM486A (2.5 µM, 48 h). Abbreviations: Dox: Doxycycline, S: serine; A: alanine; WT: wild type; KI/KI: knock-in; MEF: mouse embryonic fibroblast. ND: non-detectable. Statistics: One-tailed paired t-test was used in (f). *p < 0.05, **p < 0.01, ***p < 0.001. Error bars: Mean ± S.E.M. n= independent biological replicates (a: 3; c: 6; f: 4).
