Cadherin expression during retinal regeneration in the adult newt

The present study used an immunohistochemical technique to examine the expr ession of cadherins in the regenerating retina of adult newts. After surgic al removal of the neural retina, retinal pigment epithelial (RPE) cells pro liferate into retinal precursor cells and regenerate a fully functional ret ina. At the beginning of retinal regeneration, retinal cells originating fr om RPE cells are undifferentiated precursor cells. Both E-cadherin and R-ca dherin are expressed at the surface of these precursor cells. As regenerati on proceeds, precursor cells differentiate into retinal neurons. R-cadherin is expressed at the surface of the differentiated neurons, but E-cadherin is lost to the differentiated neurons. The difference in expression pattern suggests that each cadherin plays distinctive roles in retinal regeneratio n. And our finding that E-cadherin is expressed transiently by undifferenti ated precursor cells implies the importance of cell-cell adhesions by E-cad herin for differentiation.