Differential gene expression in cell cultures and plants of chili pepper (Capsicum annuum I.) under water stress

摘要

Chili pepper (Capsicum spp.) is a very important horticultural crop in Mexico and worldwide (FAO, 2004). Chili pepper is very sensitive to water stress and different physiological, biochemical, molecular, and genetic approaches are necessary to increase its resistance to drought. In order to study drought tolerance mechanisms at the cell level, different cell lines of chili pepper resistant to drought imposed by the presence of polyethylene glycol (PEG) in the culture medium were selected (Santos-Diaz and Ochoa-Alejo, 1994). These cell lines exhibited more negative osmotic potential, and accumulated higher levels of proline, glycine betaine, and potassium than the non-selected cell cultures. Since metabolic adjustment to drought is very often accompanied by gene expression changes, a comparative gene expression study was carried out by differential display with a PEG-resistant cell line (T7) grown in the absence (PO) or in the presence of 15% PEG (P15), and with a PEG-sensitive cell line (ST).