Photoautotrophic Culture: A Model System to Investigate the Regulation of Gene Expression in Cultured Plant Cells

Abstract

Photoautotrophism is one of the outstanding characteristics carried out by chloroplasts in plant cells. This unique property is usually not expressed in cultured plant cells, because they are grown heterotrophically in the dark together with an organic carbon source. Thus, we need the selection of the cells which show high greening to establish the photoautotrophic (PA) cells, which have developed chloroplasts and can grow in the light without any addition of carbon sources [6,8,10,21]. But the development of chloroplasts in PA cells is still limited, as shown when we compared the characteristics of cultured cells with mesophyll cells of green leaves, [7,9,22]. Little is known about the mechanisms controlling the chloroplast development especially among mesophyll cells, PA cells and other heterotrophic cells which cannot form fully differentiated chloroplasts. It is not clear whether these deficiencies are based on genetic mutations, modification of genes, or other regulatory mechanisms at the transcriptional or translational level.