Abstract
The angustilofia3 (an3) mutant of Arabidopsis thaliana shows an intriguing phenotype termed compensated cell enlargement in which defective cell proliferation post-mitotically induces enhanced cell expansion. To investigate how compensated cell enlargement is induced, we generated double mutants between an3 and mutants/transgenic plants with an increased leaf cell number, namely, grandiforlia1-D (gra1-D), jaw-D, and KNAT1 overexpressor (KNAT1 OE). These mutations were able to increase leaf cell number in the an3 background. Interestingly, jaw-D and KNAT1 OE were able to suppress compensated cell enlargement in an3 but gra1-D was not. This result suggests that a decrease in cell number is not a bona fide condition to induce compensated cell enlargement. Rather, a specific defect in particular cell proliferation pathways appears to be a key factor to induce compensated cell enlargement. We are trying to find similarity/dissimilarity between AN3/KNAT1/JAW and GRA pathways in terms of gene expression levels of several marker genes.
