Colipase and the second cysteine-rich (Cys-2) domain of Dickkopf proteins
Colipase (also called CLPS) is a cysteine-rich protein that adopts a similar fold to a cysteine-rich domain (Cys-2) of the Dickkopf (Dkk) family proteins. Colipase functions to prevent the inhibitory effect of bile salts on lipase-catalyzed intraduodenal hydrolysis of dietary long-chain triglycerides. Dickkopf proteins are a discrete class of secreted Wnt inhibitors that are required for many developmental processes, including segmentation, endoderm development, limb polarity, neural crest differentiation, kidney morphogenesis, sex determination and brain development. They possess an N-terminal signal peptide and contain two conserved cysteine-rich domains (Cys-1 and Cys-2) separated by a linker region. The Dickkopf Cys-2 domain is similar to proteins in the colipase family and it has been suggested that the Cys-2 domain of Dkks may enable interaction with lipids in order to regulate Wnt function.
Jiyao W et al.(2023). "The conserved domain database in 2023.",