Kinetic proofreading is a molecular process that occurs within the spliceosome to ensure that U1 and U2 snurps are bound to the correct sites on the DNA. This involves the hydrolysis of ATP by Prp16, which happens after a specific period of time that the spliceosome has been bound to the DNA, either resulting in the intron being excised or the pre-mRNA being released for a new spliceosome to form correctly on. Using mutant Prp16 with a slower rate of ATP hydrolysis gives more productive splicing. This is due to there being more time to align the intron correctly.
Prp16 is an RNA helicase catalysing the removal of the intron.