Plants that develop under low intensity light often display a phenotype known as the "shade tolerance syndrome". This syndrome is similar to the phenotype of plants in the juvenile phase of shoot development, but the basis for this similarity is unknown. In their new study, Dr. Mingli Xu and her colleagues from the University of Pennsylvania examined the effect of low intensity light on rosette development in Arabidopsis thaliana. They found that low intensity light prolongs the juvenile vegetative phase, and that this was associated with an increase in the expression of the master regulators of vegetative phase change. Learn more about the molecular mechanisms underlying the shade tolerance syndrome here!