Editors' ChoicePlant Science

Plastid Distress Signal

Science's STKE  08 May 2007:
Vol. 2007, Issue 385, pp. tw160
DOI: 10.1126/stke.3852007tw160

Plastids, including plant chloroplasts, are built and operated largely under the control of the nuclear genome. Largely, but not exclusively: plastids carry their own residual genome and can talk back when things go awry. Koussevitzky et al. now show that several signaling pathways that carry news of disaster from the plastid to the nucleus actually converge into one signaling pathway before the news emerges from the chloroplast. Thus, the nucleus receives a coherent report that integrates several aspects of chloroplast function. Gun1 protein is identified as a key integrator within the chloroplast, and ABI4 as a key transcription factor within the nucleus that responds to the news by altering gene transcription.

S. Koussevitzky, A. Nott, T. C. Mockler, F. Hong, G. Sachetto-Martins, M. Surpin, J. Lim, R. Mittler, J. Chory, Signals from chloroplasts converge to regulate nuclear gene expression. Science 316, 715-719 (2007). [Abstract] [Full Text]

D.-P. Zhang, Signaling to the nucleus with a loaded GUN. Science 316, 700-701 (2007). [Summary] [Full Text]