Wnt14 inhibits death of retinal precursor cells

An earlier proteomics study from our laboratory showed that Wnt14, a member of the Wnt family that regulates the development of vertebrates, was one of the proteins expressed transiently during the development of the chick retina. The purpose of this study was to determine in more detail the changes in the expression of Wnt14 during the development of the chick retina, and to investigate the biological function of Wnt14. Endogenous Wnt14 is located in the retinal ganglion cell layer, and is expressed in the chick retina on embryonic days (ED) 7, ED11, and ED15. The level of Wnt14 is transiently decreased on ED11. In vitro analysis showed that an over-expression of Wnt14 reduced the activation of caspase-3 and inhibited the death of R28 cells induced by serum deprivation or exposure to glutamate. An interferon-induced protein was identified as the protein that was bound to Wnt14. These results suggest that a stable expression of Wnt14 inhibits cell death by inactivating caspase-3 in the developing retina.