Identification and characterization of two novel brain-derived immunoglobulin superfamily members with a unique structural organization

MDGA1, an IgSF molecule containing a MAM domain, heterophilically associates with axon- and muscle-associated binding partners through distinct structural domains

“…MDGA1 was first identified as a gene that was upregulated in some human tumors (De Juan et al, 2002) and was later reported to be differentially expressed in the basilar pons of the rat (Litwack et al, 2004). Including our findings, MDGA1 has been shown to be differentially expressed among different types of cells, suggesting that it may function to alter some characteristics of the cells that express it, in a relatively general way.…”

“…The antibody recognized a single band ( Figure 2J) whose molecular mass was comparable to that of rodent MDGA1 (Litwack et al, 2004). Using this antibody, we confirmed MDGA1's LMCm-selective expression in brachial motor neurons by co-staining with an anti-Islet1 antibody that specifically demarcates the LMCm neurons (Tsuchida et al, 1994).…”

“…MDGA1's expression in regions other than the motor neurons of the spinal cord became visible around HH24 and obvious by HH26, at which time it also appeared to be restricted to certain subpopulations of spinal interneurons ( Figure 2G), as observed in rodents (Litwack et al, 2004). That MDGA1 expression was restricted to a specific subset of spinal interneurons was supported by the limited expression of the MDGA1 protein in the ventral funiculus, where only a small subset of the TuJ1-positive axons was labeled with the antibody ( Figure 2K, L).…”

“…As observed in its rat (Litwack et al, 2004) and human (Diaz-Lopez et al, 2005) orthologs, chick MDGA1 was a partially secreted, GPI-anchored extracellular molecule (Supplemental figure 1).…”

“…Hereafter, we call the gene MDGA1. Recently, the cloning of its rat homologues and its expression profiles in rat brain were independently reported (Litwack et al, 2004).…”