Nitric oxide (NO) is an important signaling molecule in animal systems, but its role in plants is poorly understood. He et al. report that NO controls flowering in the plant Arabidopsis thaliana. Exposure to exogenous NO delayed flowering, and mutation of a gene called nox1--a putative phosphoenolpyruvate/phosphate translocator--resulted in delayed flowering and increased NO production. The mutant also exhibited altered expression of the target genes of two separate pathways that control the vegetative-to-reproductive phase transition in response to either external or internal cues. Thus, NO may integrate and fine tune the flowering response to both environmental and internal stimuli.
Y. He, R.-H. Tang, Y. Hao, R. D. Stevens, C. W. Cook, S. M. Ahn, L. Jing, Z. Yang, L. Chen, F. Guo, F. Fiorani, R. B. Jackson, N. M. Crawford, Z.-M. Pei, Nitric oxide represses the Arabidopsis floral transition. Science 305, 1968-1971 (2004). [Abstract] [Full Text]
