Cadherin expression during retinal regeneration in the adult newt

Abstract

The present study used an immunohistochemical technique to examine the expression of cadherins in the regenerating retina of adult newts. After surgical removal of the neural retina, retinal pigment epithelial (RPE) cells proliferate into retinal precursor cells and regenerate a fully functional retina. At the beginning of retinal regeneration, retinal cells originating from RPE cells are undifferentiated precursor cells. Both E-cadherin and R-cadherin are expressed at the surface of these precursor cells. As regeneration 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 regeneration. And our finding that E-cadherin is expressed transiently by undifferentiated precursor cells implies the importance of cell-cell adhesions by E-cadherin for differentiation.