Characterization of suppressors of fat-like cadherin CDH-4 in context of axon guidance during embryonic development

Developing the nervous system requires axons to grow and connect to specific targets, forming neuronal circuits, through axon navigation. One of the genes controlling axon navigation is the fat-like cadherin CDH-4, a member of the cadherin superfamily. To identify genes acting together with cdh-4, mutants suppressing the axon guidance defects of cdh-4 mutants were isolated previously. The goal of this thesis was to characterize and identify these suppressor genes. Five suppressors were studied in detail. They partially suppressed axon guidance and movement defects observed in the cdh-4 mutants. Three suppressor genes were identified: math-48, a functionally uncharacterized gene, prp-6 and prp-8, both encoding components of the spliceosome. A previous study documented changes in expression of several hundred genes when prp-6 or prp-8 are partially inactivated. This suggests that the suppression effect might be mediated by upregulation of one or more genes, compensating for the loss of CDH-4.