This gene encodes a protein whose expression was found to increase in cultured cells at high density but not during growth arrest. This gene was also shown to have increased expression in cells overexpressing HER-2/neu proto-oncogene. The protein contains an SUI1 domain. In budding yeast, SUI1 is a translation initiation factor that along with eIF-2 and the initiator tRNA-Met, directs the ribosome to the proper translation start site. Proteins similar to SUI have been found in mammals, insects, and plants.