Component of a complex that acts as a quorum sensing protein regulating discoidin gene expression during growth and development. Its function in the complex is unclear as it has no ability to induce discoidin during growth and development by itself. Forms a complex with psiF/dicA. According to PubMed:15947191, it is secreted in the conditioned medium. However, prediction tools clearly predict a transmembrane domain. In some conditions, it may be cleaved and secreted in the conditioned medium, which would explain the discrepancy.