Integrator Complex Subunit 1 (INTS1)

INTS1 is a subunit of the Integrator complex, which associates with the C-terminal domain of RNA polymerase II large subunit (POLR2A) and mediates 3-prime end processing of small nuclear RNAs U1 (RNU1) and U2 (RNU2).By sequencing clones obtained from a size-fractionated adult brain cDNA library, Nagase et al. (2000) cloned INTS1, which they designated KIAA1440. The deduced protein contains 1,377 amino acids. RT-PCR ELISA detected highest expression in whole adult brain, with moderate to high expression in all other adult and fetal tissues and all specific brain regions examined.By SDS-PAGE of proteins that copurified with INTS11 (CPSF3L) in HEK293 cells, Baillat et al. (2005) identified INTS1 as a subunit of the Integrator complex.