Recombinant Mouse Olfactomedin-1/Noelin-1 Protein, CF

Noelin-1 (neuronal olfactomedin-related endoplasmic reticulum-localized-1), also known as Olfactomedin-1 or pancortin, is a 75 kDa secreted extracellular matrix glycoprotein expressed in the brain (1 - 3). Alternate promoter usage and splicing creates four forms of Noelin (Noelin 1 - 4) that are combinations of a common central region with alternate N- and C-termini (3, 4). Noelin-1 is the longest of the four isoforms, encoding a 16 amino acid (aa) signal sequence and a 469 aa mature protein with a coiled-coil region for multimerization and an olfactomedin-like domain. The shortest isoforms, Noelin-3 and -4, are truncated within the coiled-coil region and lack the olfactomedin-like domain (4). In the species tested, these isoforms appear to oppose actions of the longer isoforms (5). All isoforms are capable of forming homo- or heterodimers through cysteines in their common central region (2). The C-terminus of Noelin-1 (mouse aa 482 - 485) contains a putative endoplasmic reticulum retention sequence that has not been included in the R&D Systems protein (6). Mouse Noelin-1 (aa 17 - 481) shares > 99%, 99%, 97%, 96% and 93% aa identity with corresponding regions of rat, human, opossum, chicken and Xenopus Noelin-1, respectively. In vivo expression patterns differ somewhat between species (1). In chick early development, Noelin-1 shows highest concentration in areas that produce neural crest cells and is produced by migrating neural crest cells (7). Overproduction of Noelin-1 prolongs neural crest cell formation (7). Noelin-1 is also expressed in mouse neural crest, but not frog (1 - 3). All three species express Noelin-1 later in differentiating neural tissues in the spinal cord, brain and cranial ganglia (1 - 3).