This gene encodes a member of the R-spondin family of proteins. These proteins are secreted ligands of leucine-rich repeat containing G protein-coupled receptors that enhance Wnt signaling through the inhibition of ubiquitin E3 ligases. A chromosomal translocation including this locus that results in the formation of a gene fusion has been identified in multiple human cancers. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2015].