Integrator complex subunit 9 (INTS9)

Integrator complex subunit 9 (INTS9) is a non-catalytic component of the multi-protein Integrator complex, which is essential for the 3'-end processing of uridine-rich small nuclear RNAs (UsnRNAs), enhancer RNAs (eRNAs), and participates in transcription regulation by RNA polymerase II[1][2][3][5]. INTS9 is a paralog of CPSF100 and shares overall structure with active nucleases of the metallo-β-lactamase/β-CASP family, but due to mutations in key conserved motifs, INTS9 is catalytically inactive ("pseudonuclease") and instead functions as a structural and regulatory scaffold within the complex[2][3]. The protein tightly associates with the endonuclease INTS11, and this dimerization is crucial for Integrator complex function in snRNA 3'-end processing and formation of a quality-control checkpoint during transcription elongation[1][2][3][5]. Variants in INTS9 are linked to Galloway-Mowat syndrome, but no drugs are known to act directly on INTS9 or use it as a therapeutic or diagnostic biomarker[5].

Other names

RC74Int9RC-74FLJ10871CPSF2Lprotein related to CPSF subunits of 74 kDaINT9