Final answer:
The malate dehydrogenase isoform found in the cytoplasm is MDH1, which is important in metabolism and stress resistance in plants.
Step-by-step explanation:
Malate Dehydrogenase Isoforms in the Cytoplasm
The malate dehydrogenase isoform that is typically found in the cytoplasm is MDH1. This enzyme plays a crucial role in the citric acid cycle by catalyzing the oxidation of malate to oxaloacetate and producing NADH. Over-expression of cytosolic NAD-dependent MDH has been reported to promote growth and tolerance to cold and high salinity in various plants. For example, MDH expression may increase the resistance by altering the distribution of carbon and energy in plants treated with salicylic acid.