Abstract
Abstract: :
Purpose: Evidence is emerging that stem cells recruit multiple signaling pathways to maintain their proliferative and uncommitted state. It is likely that this strategy is also operational in the vertebrate eye. Intercellular signaling pathways are important role in developmental events in the retina and the endogenous regulators and modulators of various signaling molecules precisely regulate their function in vitro and in vivo. We have previously shown that Wnt signaling play an important role in the maintenance of retinal stem cells. Recently, a novel secreted molecule, Wise has been reported in Xenopus which can be an activator as well as inhibitor of Wnt signaling in a context–dependant manner. Here in this study, we are using the cultured retinal stem cells/progenitors as model system to investigate the influence of Wise on the canonical Wnt signaling pathway during proliferation and differentiation. Methods: cDNA obtained from adult retina was used to clone the rat Wise cDNA. RT–PCR and in situ hybridization analysis were carried out to detect the temporal and spatial pattern of expression. To carryout the functional analysis of Wise in cultured retinal stem cells/progenitors, Wise cDNA has been cloned into the expression vectors. Results: The deduced aminoacid sequence of the rat Wise is homologous to the mouse and chick Wise. Transcripts corresponding to Wise were detected during retinal development and their pattern of expression correlates with the two stages of retinal hitogenesis. We are currently examining the expression of Wise in cultured retinal stem cells/progenitors and determining the functional involvement in their proliferation and differentiation. Conclusions: Wise is expressed during retinal development and may influence Wnt signaling–mediated regulation of retinal stem cells/progenitors.
Keywords: retinal development • proliferation • regeneration