Co-suppression of NbClpC1 and NbClpC2 in Tobacco Lowers its Photosynthetic Capacity via Altered Leaf Structure

The Clp protease is the central protein degradation machinery in the plastids of a plant cell, with ClpC1 and ClpC2 being chaperonic proteins for the Clp protease. Md. Korean researchers led by Sarafat Ali and Youngjae Yu of Yeungnam University and Chungnam National University, respectively, investigated the functions of ClpC1 and ClpC2 in photosynthesis by co-suppression of both genes in Nicotiana benthamiana.

Co-suppression of NbClpC1 and NbClpC2 in N. benthamiana resulted in abnormal structure with severe chlorotic leaves, stunted growth and reduced numbers of stomata, resulting in lowered photosynthetic capacity. Physiological characters related to photosynthesis, such as leaf CO₂ assimilation rate, were also significantly lower in the leaves of transgenics compared to the control. Analysis revealed that the leaves of the transgenics had coarsely packed mesophyll cells.

The results strongly suggest that ClpC1 and ClpC2 are pivotal in photosynthetic competence by affecting the structure of leaves and numbers of stomata.

For more information, read the full article in Plant Omics Journal.