OLIG1 (Oligodendrocyte transcription factor 1) is a transcription factor necessary for neonatal myelin repair and plays a role in neural progenitor cell production, neural differentiation and oligodendrocyte formation, and injury response and repair in the brain. It is also involved in regulating cell motility via TGF-beta signaling. In immunohistochemistry, OLIG1 has nuclear positivity throughout the normal central nervous system, and in cancers it has high positivity in oligodendrogliomas, low to medium expression in astrocytomas, and variable positivity in glioblastomas. OLIG1 is largely absent in other tissues and organs. References: Ann Neurol. 2017 Apr;81(4):560-571, PMID: 28253550; J Biol Chem. 2013 Jun 28;288(26):18911-22, PMID: 23720758; Nat Rev Neurosci. 2012 Dec;13(12):819-31, PMID: 23165259; Neuron. 25 (2): 331–43, PMID: 10719889; Proc Natl Acad Sci U S A. 2001 Sep 11;98(19):10851-6, PMID: 11526205;