Molecular scissors caught in the act: Describing the function of tRNA splicing endonuclease TSEN based on its structure

In all living organisms, the biomolecule transfer RNA (tRNA) plays a fundamental role in protein production. tRNAs are generated from precursor molecules in several steps. The enzyme tRNA splicing endonuclease (TSEN), among other things, catalyzes one step in this process. Mutations in TSEN lead to a neurodegenerative disorder called pontocerebellar hypoplasia, which is associated with severe disabilities and early death.