title: Relative mobility and activity of leaf malate dehydrogenase in flax (Linum usitatissimum) genotrophs and genotypes.
abstract: Malate dehydrogenase (MDH) band relative mobility (Rm) and activity were examined in leaf extracts of Durrant's flax genotrophs, L and S, and flax genotypes, R and M. MDH activity in leaves from just below the inflorescence was higher in the two smaller, sparsely branched plant types, S and M, than in the larger, more branched plant types, L and R. The MDH electrophoretic banding pattern in flax leaf extracts consisted of three major anionic bands, MDH-1, MDH-2, and MDH-3. No Rm differences were detected between corresponding isozymes of genotypes R and M. For the genotrophs, however, all three bands of S migrated faster than the corresponding bands of L. Codominance was absent in F1 hybrids; S Rm was dominant for MDH-2 and MDH-3 and L Rm was dominant for MDH-1. The observations suggest that MDH Rm in L and S may be controlled by a modifier locus (or loci). Previous studies indicate that a modifier locus may also control heritable genotrophic differences in peroxidase (PER) and acid phosphates (AP) Rm. The three enzyme systems are compared.
authors.affiliation: Department of Biology, Wilfrid Laurier University, Waterloo, Ontario, Canada.
authors.forename: M A
authors.initials: MA
authors.lastname: Fieldes
mesh_terms: D004586:Electrophoresis / Q000379:methods; D005838:Genotype; D007527:Isoenzymes / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D007700:Kinetics; D008291:Malate Dehydrogenase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D007527:Isoenzymes; D008291:Malate Dehydrogenase