This gene encodes a protein with a proline-rich domain. This gene is located in a region of chromosome 22 reported to contain a tumor suppressor gene that may be involved in breast and colorectal tumorigenesis. The protein is a component of the mammalian target of rapamycin complex 2 (mTORC2), and it regulates platelet-derived growth factor (PDGF) receptor beta expression and PDGF signaling to Akt and S6K1. Alternative splicing and the use of alternative promoters results in transcripts encoding different isoforms. Read-through transcripts from this gene into the downstream Rho GTPase activating protein 8 (ARHGAP8) gene also exist, which led to the original description of PRR5 and ARHGAP8 being a single gene. [provided by RefSeq, Nov 2010]