Recruits the ubiquitination machinery to RNA polymerase II for polyubiquitination, removal and degradation, when the transcription-coupled nucleotide excision repair (TC-NER) machinery fails to resolve DNA damage (PubMed:35633597). Plays an important role in the activity of long-term repopulating hematopoietic stem cells (LT-HSCs) (By similarity). Is a regulator of stress granule assembly, required for their efficient formation (PubMed:29395067, PubMed:35977029). Required for proper brain development and neocortex lamination (By similarity).