Y-box binding protein 1 (YBX1) is one of the cis acting elements that plays a role in regulating the expression of HLA class II genes. YBX1 is very important in regulating PTP1B expression. It can bind to splicing sites to mediate pre mRNA alternative splicing regulation. It serves as both a DNA and RNA binding protein and is involved in many cellular processes, including regulating transcription and translation, pre mRNA splicing, DNA compensation, and mRNA packaging. This protein is also a component of the messenger ribonucleoprotein (MRNP) complex and may play a role in microRNA processing. This protein can be secreted through non classical pathways and used as an extracellular mitogen. The abnormal expression of this gene is associated with cancer proliferation in many tissues. This gene may be a prognostic marker for poor prognosis and drug resistance in certain cancers. Alternative splicing can lead to multiple transcript variants. The pseudogene of this gene has been found on multiple chromosomes.
