Abstract
To understand vascular pattern formation, we have analyzed van3 mutants of Arabidopsis characterized by fragmented veins. We have shown that VAN3 encodes an AZAP type ARF (ADP ribosylation factor)-GAP (GTPase activating protein) that function in the trans Golgi network. As the first step toward elucidating the function of Arabidopsis AZAP type ARF-GAPs (AZAPs) systematically, here we observed the expression patterns of all the four Arabidopsis AZAPs using the GUS reporter genes.
In leaf primordia, VAN3 was expressed uniformly. As the primordia developed, the expression became restricted to vasculatures. Similar expression patterns were observed in the other AZAPs. In roots, however, VAN3 is expressed in the elongation zone, while the other AZAPs are expressed in QC and columella cells. These results indicate that AZAPs function in different root cells. Now efforts are underway to analyze knockout mutants of AZAPs. Taken together, we will discuss the role of AZAPs in plant development.
