SF3B1 phosphorylation is an evolutionarily conserved step in spliceosome activation carried out by the divergent, OTS964-insensitive kinase CRK9 in trypanosomes
Kazuya Machida, Priyanka Rattan, Sofia Cassidento, Nuala Peterman, Bing Hao, Arthur Günzl
The paper shows that CRK9, a trypanosome kinase, phosphorylates SF3B1 TP motifs to activate the spliceosome, conserving a function previously known in CDK11, and is insensitive to OTS964.
Nucleic Acids Research · May 15, 2026Peer-reviewedMolecular Biology