Predicted to enable RNA polymerase II general transcription initiation factor activity and protein N-terminus binding activity. Predicted to be involved in nucleotide-excision repair; phosphorylation of RNA polymerase II C-terminal domain; and transcription by RNA polymerase II. Predicted to act upstream of or within DNA repair. Predicted to be located in nucleoplasm. Predicted to be part of core TFIIH complex portion of holo TFIIH complex; transcription factor TFIID complex; and transcription preinitiation complex. Is expressed in several structures, including blastocyst; genitourinary system; and submandibular gland primordium. Orthologous to human GTF2H3 (general transcription factor IIH subunit 3). [provided by Alliance of Genome Resources, Apr 2022]