Abstract
Abstract: :
Purpose: Deletion of Cx50 produces microphthalamia with nuclear cataracts. To determine if these two traits were influenced by genetic background, and were dependent on each other, mice carrying the Cx50 deletion in two different strains were generated and the growth defect and severity of cataracts were analyzed. Methods: Cx50 knockout mice were generated in the 129SvEv strain, and back-crossed into the C57Bl/6 genetic background. In order to analyze the influence of genetic background on the observed phenotype, postnatal lens growth, lens clarity, lens histology and crystallin solubility were determined and compared between the two strains of Cx50 KO mice. Results: We found that the growth deficiency persisted regardless of genetic background, but genetic modifiers that differentially altered the solubility of crystallin proteins influenced the severity of cataracts. Expression levels of Cx46 were similar in all animals regardless of genetic background, indicating that the differences were not due to a compensatory up-regulation of Cx46. Conclusions: Taken together, these data indicate that the two components of the Cx50 phenotype are independent of each other, and that cataract severity is under the influence of an unidentified genetic modifier.
Keywords: animal model • gap junctions/coupling • cell-cell communication