Members of the lipocalin family, such as LCN9, have a common structure consisting of an 8-stranded antiparallel beta-barrel that forms a cup-shaped ligand-binding pocket or calyx. Lipocalins generally bind small hydrophobic ligands and transport them to specific cells (Suzuki et al., 2004 [PubMed 15363845]).[supplied by OMIM, Aug 2009].