Functional analysis of R-cadherin in developing zebrafish (Danio rerio) retinal ganglion cells. (Medical Science and Health Poster Session 09:00 AM-10:00 AM).

Kotradi, Shannon M. ; Liu, Qin

BOARD 12

Cadherins are [Ca.sup.2+]-dependent cell adhesion molecules that are thought to play key roles in differentiation, segregation and compartmentalization of the vertebrate central nervous system. Most cadherins contain extracellular, transmembrane and cytoplasmic domains, all of which are necessary to mediate proper cell adhesion. While temporal and spatial expression studies have implicated R-cadherin as playing a role in developing zebrafish retinal ganglion cells (RGCs), to date there have been no functional analyses on the subject. To determine R-cadherin function in zebrafish RGC development, Reverse Transcription-Polymerase Chain Reaction and ligation techniques were used to generate a dominant negative construct (Rcad[DELTA]C) that encodes for the extracellular and transmembrane domains of R-cadherin with a reporter gene in place of the cytoplasmic domain. Subsequently, Rcad [DELTA]C was injected into 1-4 cell stage zebrafish embryos and transfected RGCs were detected using an antibody against the reporter gene. RcadsC transfected RGCs (n=73) had a significantly fewer average number of dendritic and axonal processes (2.63 compared to 16.54; p<0.001) than RGCs in the control group (n= 54). Average total length of processes of Rcad [DELTA]C transfected RGCs was also significantly lower than that of the control group (5.83 [micro]m compared to 33.13 [micro]m; p<0.001). These results suggest that R-cadherin plays an important role in the development and differentiation of zebrafish retinal ganglion cells.

SHANNON M. KOTRADI SKOTRAD@UAKRON.EDU, QIN LIU QLIU@UAKRON.EDU, DEPT OF BIOLOGY, UNIVERSITY OF AKRON, AKRON OH 44325-3908