This family includes WD repeat and coiled-coil-containing protein (WDCP, previously known as C2orf44), which is found in eukaryotes and consists of around 721 amino acids. The N-terminal contains two WD (tryptophan-aspartic acid) repeats (WD1 and WD2). WD repeats may be involved in a range of biological functions including apoptosis, transcriptional regulation and signal transduction. The C-terminal contains a proline-rich sequence (PPRLPQR), and is predicted to have leucine-rich coiled coil region (CC) [1]. WDCP was identified in a proteomic screen to find signalling components that interact with Hck (hematopoietic cell kinase), a non-receptor tyrosine kinase. WDCP was shown to bind tightly and specifically to the SH3 domain of Hck in U937 human monocytic cells. WDCP was also shown to exist as an oligomer when expressed in mammalian cells. While the function of WDCP is unknown, it has been identified in a gene fusion event with anaplastic lymphoma kinase (ALK) in colorectal cancer patients [1].

1: Molecular characterization of WDCP, a novel fusion partner for the anaplastic lymphoma tyrosine kinase ALK. Yokoyama N, Miller WT; Biomed Rep. 2015;3:9-13. PMID:25469238