The forkhead gene family of Caenorhabditis elegans

The forkhead genes encode a family of transcriptional regulators with important roles in the control of animal development. The genomic sequence has revealed Caenorhabditis elegans has 15 forkhead genes of which six had been experimentally characterised previously. The remaining nine have now been investigated by RNAi and reporter gene expression pattern analysis. Two (B0286.5 and F26B1.7) have key developmental roles, four (F26D12.1, K03C7.2, F40H3.4 and C25A1.2) are expressed in, and may function in, the nervous system and three (C29F7.4, C29F7.5 and F26A1.2), which are closely related to each other, do not appear to be essential. Conservation with forkhead genes in the closely related nematode Caenorhabditis briggsae does not appear to correspond completely with demonstrated functionality in C. elegans. Comparisons of expression patterns and RNAi/mutant phenotypes for all 15 C. elegans forkhead genes reveal the potential complexity of functional interactions for this gene family.