A CELLULAR AND PSYCHOLOGICAL CLOCK SETS T HE PACE OF THE LIFE OF THE NEMATODE CAENORHABDITIS-ELEGANS

Many developmental and behavioral features of living organisms appear to be precisely timed by internal mechanisms which are referred to as ''biological clocks''. In the nematode Caenorhabditis elegans four mat ernal-effect genes which appear to be required for the function of sev eral distinct biological clocks have been identified. The consequences of mutations in the gene clk-1 have been studied in most detail. Thes e mutations result in a mean lengthening of embryonic and post-embryon ic development, the cell cycle period and life span, as well as the pe riods of behavioral cycles such as the defecation, swimming and pumpin g cycles. This review focuses on the hypothesis that the phenotype of genes like clk-1 reveals the existence of a central mechanism involved in synchronizing the activities of a variety of organismal features.