Brorin/VWC2: ProductsBrorin (brain-specific chordin-like protein), also called VWC2, is an ~46 kDa glycoprotein that is a member of the Chordin family of secreted BMP regulators. The human Brorin cDNA encodes 325 amino acids (aa) including a 27 aa signal sequence and a 298 aa secreted mature protein with two VWFC domains. These domains contain a pattern of 10 cysteine residues that is conserved in other family members, with the remaining aa sequence sharing little identity. Human Brorin shares 90%, 91%, and 95% aa sequence identity with mouse, rat, and equine Brorin, respectively. It also shares aa identity with VWC2L (Brorin-like) of 37% overall and 62% within the VWFC domains. Brorin is predominantly expressed in embryonic and adult neural tissues in the mouse. Expression of Brorin mRNA is concentrated in neurons within the diencephalon and medulla oblongata but is not detected in the developing cerebral cortex. Brorin binds and antagonizes BMPs, interacting via the VWFC domains. It promotes neurogenesis in mouse neural precursors. Knockdown of Brorin in zebrafish embryos results in morphological abnormalities in the brain and eye.