Component of the cell wall. Covalently-linked GPI-modified cell wall protein (GPI-CWP) found in young daughter cells. Down-regulated during anaerobic growth. Extensively O-glycosylated. The GPI-anchor is attached to the protein in the endoplasmic reticulum and serves to target the protein to the cell surface. There, the glucosamine-inositol phospholipid moiety is cleaved off and the GPI-modified mannoprotein is covalently attached via its lipidless GPI glycan remnant to the 1,6-beta-glucan of the outer cell wall layer. Covalently linked to beta-1,3-glucan of the inner cell wall layer via an alkali-sensitive ester linkage between the gamma-carboxyl group of glutamic acids, arising from a specific glutamine within the PIR1/2/3 repeat, and hydroxyl groups of glucoses of beta-1,3-glucan chains. Present with 1590000 molecules/cell in log phase SD medium. Belongs to the SRP1/TIP1 family.