Characterizing Arabidopsis thaliana mutant lines that affect leaf shape and vein pattern

Abstract

An optimum leaf shape and vein pattern is necessary for vascular plant success. The isolation of leaf morphological mutants of Arabidopsis thaliana has been used for leaf development studies. Auxin is a signal molecular that regulates plant development and growth processes. I have analyzed four mutations in detail, and I suggest that they all have defects in auxin regulated plant development processes. Mutant 115-11-21-4 is an allele of FKD1 with frequent distal free-ending veins. Mutant 31-83-4-3 likely has increased auxin flux through secondary veins and increased downward auxin transport through the shoot, possibly due to increased PIN1 expression and/or altered PIN1 localization. Mutant 32-2-4 likely has increased auxin activity at marginal auxin convergence points resulting in the formation of increased leaf serrations. Mutant 33-7-5(4) may have a global reduction in auxin biosynthesis or response, thus the whole plant is weak and pale, with slower shoot and root growth rate and gravitropic response.