Pervasive translational control of photosynthesis genes during photomorphogenesis is acquired by C4 genes

Abstract

C4 photosynthesis allows increased efficiency and has evolved in more than sixty-six plant lineages. Underpinning this repeated appearance of the C4 pathway is a major transcriptional reprogramming of photosynthesis genes. Here we investigated whether evolution has also significantly modified translational control by defining the translational dynamics of C3 rice and C4 sorghum during photomorphogenesis. In the dark rice photosynthesis transcripts are low abundance but highly translated. After exposure to light translational efficiency declines. The same phenomena occur in sorghum but in addition C4 cycle genes show this response. We propose a model in which translational control of photosynthesis genes permits a rapid response to light and that this translational regulation is gained by C4 genes during the evolution of the C4 pathway.