Mesd is a family of highly conserved proteins found from nematodes to humans. The final C-terminal residues, KEDL, are the endoplasmic reticulum retention sequence as it is an ER protein specifically required for the intracellular trafficking of members of the low-density lipoprotein family of receptors (LDLRs) [1]. The N- and C-terminal sequences are predicted to adopt a random coil conformation, with the exception of an isolated predicted helix within the N-terminal region, The central folded domain flanked by natively unstructured regions is the necessary structure for facilitating maturation of LRP6 (Low-Density Lipoprotein Receptor-Related Protein 6 Maturation) [2].

1: Boca, an endoplasmic reticulum protein required for wingless signaling and trafficking of LDL receptor family members in Drosophila. Culi J, Mann RS; Cell. 2003;112:343-354. PMID:12581524

2: Requirement for natively unstructured regions of mesoderm development candidate 2 in promoting low-density lipoprotein receptor-related protein 6 maturation. Koduri V, Blacklow SC; Biochemistry. 2007;46:6570-6577. PMID:17488095