Towards map‐based cloning of two genes involved in iron acquisition and metabolism in tomato

Abstract

Iron is an important micronutrient element of plants. For mobilization and uptake of iron from soil, plants use different active mechanisms. In the last two decades, many researches have focused on the physiological and biochemical basis of iron uptake and metabolism in plants. Little is known about genes involved in the uptake process from soil and their regulation in vivo. To study molecular biology of iron uptake and metabolism in strategy I plants, the mutants chloronerva (chln) and T3238fer (fer) described in tomato (Lycopersicon esculentum Mill.) are very informative mutants. The fer gene is epstatic over the chln gene in double mutants and controls the whole process of iron deficiency response reaction in strategy I plants while the chln gene is responsible for synthesis of the non‐protein amino acid, nicotianamine, which is a key substance in iron metabolism of all higher plants. We try to isolate the both genes by map‐based cloning approach. In this paper we describe our strategy and an actual state of progress for the isolation of the fer and chln genes in tomato. The isolation of the two genes would represent an important first step for understanding the molecular mechanisms controlling strategy I iron‐uptake responses.