Abstract
To dissect vascular pattern formation genetically, we have isolated and analyzed van mutants of arabidopsis that are characterized by fragmented minor veins. Here we report putative auxin distribution in relation to vein development of the van3 mutant and genetic interaction between VAN3 and auxin-related genes.
Putative auxin distribution was analyzed using a fusion gene of auxin-inducible promoter and reporter, DR5::GUS. In the formation of tertiary veins of wild type plants and the van3 mutant, GUS staining was observed as a dotted pattern in the provascular cell and staining cells were interspersed between secondary veins but the number of staining cells of the van3 mutant was reduced substantially. Next, we generated double mutants of van3 with pin1, gn and mp. The van3pin1 double mutant displayed the sum of two mutant phenotypes, suggesting that VAN3 and polar auxin transport system do not act in the same pathway toward vascular pattern formation.
