RNA endoribonuclease involved in perinuclear mRNP quality control%3B involved in perinuclear mRNP quality control via the turnover of aberrant%2C unprocessed pre-mRNAs%3B interacts with subunits of THO/TREX%2C TREX-2%2C and RNA polymerase II%3B contains a PIN (PilT N terminus) domain