FREM1 Full-Length MS Protein Standard (NP_659403), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. This gene encodes a basement membrane protein that may play a role in craniofacial and renal development. Mutations in this gene have been associated with bifid nose with or without anorectal and renal anomalies. Alternatively spliced transcript variants encoding different isoforms have been described. PubMed ID 19940113 describes one such variant that initiates transcription within a distinct, internal exon; the resulting shorter isoform (named Toll-like/interleukin-1 receptor regulator, TILRR) is suggested to be a co-receptor of the interleukin 1 receptor family and may regulate receptor function and Toll-like receptor/interleukin 1 receptor signal transduction, contributing to the control of inflammatory response activation.