Mouse RGM-A Biotinylated Antibody

Mouse repulsive guidance molecule (RGM-A) is a 33 kDa GPI-linked member of an expanding RGM-related family of neuronal and muscle-expressed membrane proteins (1). It is synthesized as a 454 amino acid (aa) preproprotein that contains a 47 aa signal sequence, a 122 aa N-terminal prosegment, a 258 mature region and a 27 aa C-terminal prosegment (2, 3). The N-terminal prosegment contains an RGD tripeptide and the molecule’s only two potential N-linked glycosylation sites. The mature segment shows an abbreviated von Willebrand factor domain. Proteolytic processing occurs at an aspartic acid-proline bond, creating a predicted 32 kDa mature region (2). The mature region of mouse RGM-A is 93% and 87% aa identical to human and chick mature region RGM-A, respectively. When compared to mouse RGMb and c, the mature region of mouse RGM-A shows 77% and 76% aa identity, respectively (2, 3). Recombinant chick RGM has been reported to induce collapse of temporal but not nasal growth cones, and to repel temporal retinal axons in vitro. This suggests a role in the development of the retina-superior colliculus connection. In mice, however, this activity is not so obvious, and the function in this system is uncertain (3). Alternatively, in mice, RGM-A is said to be needed for neural tube closure (3), while chick RGM-A is reported to be responsible for the layered segmentation of entorhinal cortical projections to the hippocampus (4). The receptor for RGM is reported to be neogenin (5, 6).