Cacao

Your annotation doesn't really specify which gene is a structural constituent of the myelin sheath, but I don't think you can conclude from the paper figures that the proteins actually are a structural constituents, just that they are localized there. However, there isn't a GO term for localization to myelin membrane, so I propose that we change this annotation to GO:0072659, localization to the plasma membrane, as Figure 4 shows that by IDA, both proteins discussed in the paper (P0 and PMP22) are localized to the plasma membrane by staining in transformed HeLa cells. Figure 4 B specifically shows signal from both proteins at cell-cell contact points - the plasma membrane, and Figure 4C-E shows signal from both proteins matching with signal from and antibody to the extracellular domain of the cell.

The following Reference, Evidence Code and Notes better fit the GO Term.

Reference PMID: 6161678 Evidence Code: IDA Notes: From Abstract " The major glycoprotein bands in PNS myelin, in addition to the PO glycoprotein at 28K, exist at 23K and 19K, as shown by gel electrophoresis in dodecyl sulfate. These glycoproteins, isolated by gel filtration in 2% dodecyl sulfate, show identity to the PO glycoprotein in their monosaccharide profile and overlapping tryptic peptides on peptide mapping. We conclude that both the 23K and 19K glycoproteins are derived from the PO glycoprotein by in situ proteolysis; the 23K glycoprotein has the identical amino terminal sequence. The 19K glycoprotein, beginning with amino-terminal methionine, is identical with the TPO glycoprotein, shown previously to originate from tryptic hydrolysis of the PO glycoprotein in isolated myelin. A tryptic glycopeptide containing 27 amino acids was isolated from the PO glycoprotein and sequenced. It contained a relatively high proportion of aspartic acid (four residues) and glutamic acid (two residues), thus exhibiting a high negative charge. We conclude that the total carbohydrate of the PO, 23K, and 19K glycoproteins does indeed exist as a single nonasaccharide moiety linked through N-acetylglucosamine to Asp-14 of the glycopeptide in a N-glycosidic linkage. These results further support the role of the PO glycoprotein as a typical amphipathic membrane protein."

Add more specific notes