Calcineurin is a calcium/calmodulin-dependent Serine/Threonine protein phosphatase and is well known to have diverse cellular functions in different organisms. The previous studies have shown that calcineurin (TAX-6/CNB-1) is involved in body size regulation in C. elegans. However, the exact mechanism is still unknown. In order to identify specific kinase(s) antagonizing calcineurin in regulating body size, we performed targeted RNAi screening. Since
tax-6 is predominantly expressed in neurons and the neuronal expression of
tax-6 is sufficient to rescue the small body size of
tax-6 mutant, we selected kinase candidates, which have shown neuronal expression. Candidates were further selected by availability for bacterial feeding RNAi clone in RNAi library. For the feeding RNAi, we used VH624 strain. We fed to VH624 strains which are more efficient to RNAi in neuron, with bacteria expressing RNAi of kinase candidates and
tax-6 RNAi. In F2 generation after RNAi feeding, we measured body length of one day old adults and selected candidates which rescued small phenotype of
tax-6 mutants. We found that RNAi feeding of 22 kinase candidates rescued
tax-6 phenotype of small body size. To confirm whether positive hits, we generated RNAi plasmids containing partial cDNA of each candidates. We showed that all candidates rescued
tax-6 RNAi small phenotype.