IntS11 is the catalytic component of integrator complex (INT), which is involved in the small nuclear RNAs (snRNA) U1 and U2 transcription and in their 3'-box-dependent processing. This is the C-terminal domain of IntS11 which interacts with the C-terminal of IntS9 (Pfam:PF21382), which is a crucial interaction for the role of INT in snRNA 3'-end processing [1,2]. IntS11 is responsible of the endonuclease activity of INT [1-3].

1: Molecular basis for the interaction between Integrator subunits IntS9 and IntS11 and its functional importance. Wu Y, Albrecht TR, Baillat D, Wagner EJ, Tong L; Proc Natl Acad Sci U S A. 2017;114:4394-4399. PMID:28396433

2: Structure of the catalytic core of the Integrator complex. Pfleiderer MM, Galej WP; Mol Cell. 2021;81:1246-1259. PMID:33548203

3: Identification of Integrator-PP2A complex (INTAC), an RNA polymerase II phosphatase. Zheng H, Qi Y, Hu S, Cao X, Xu C, Yin Z, Chen X, Li Y, Liu W, Li J, Wang J, Wei G, Liang K, Chen FX, Xu Y; Science. 2020; [Epub ahead of print] PMID:33243860