tej defines a role for poly(ADP-ribosyl)ation in establishing period length of the Arabidopsis circadian oscillator

In a genetic screen for altered circadian period length in Arabidopsis, we isolated a mutant with a long free-running period. The tej mutation acts independently of light quality and quantity. It affects clock-controlled transcription of genes in Arabidopsis and alters the timing of the photoperiod-dependent transition from vegetative growth to flowering. Map-based cloning of TEJ identified a poly(ADP-ribose) glycohydrolase (PARG). An inhibitor of poly(ADP-ribosyl)ation rescued the period phenotype of tej mutant and shortened the period length of wild-type plants. Posttranslational poly(ADP-ribosyl)ation of an oscillator component may contribute to setting the period length of the Arabidopsis central oscillator.