Chromosomal duplication in the grandifolia-D mutants of Arabidopsis thaliana, expression data

The number of cells in an organ is a major factor for the determination of organ size. However, genetic basis of cell number determination is not well understood. Three grandifolia-D (gra-D) mutants of Arabidopsis thaliana developed huge leaves containing two- to three-fold increased number of cells of the wild type. Tiling array and microarray analysis of gra-D mutants suggested that genes found in a lower part of chromosome 4 were upregulated, suggesting the occurrence of segmental chromosomal duplications in the gra-D mutants. These region contain positive regulators of cell proliferation such as AINTEGUMENTA (ANT) and cyclin genes such as CYCD3;1. Total RNAs were extracted using RNeasy plant mini kit (Qiagen) from vegetative part of seedlings at stage 1.03 grown in vitro. RNAs from three biological repeats of wild type (wt, control) and the 3 grandifolia mutants (gra1-D, gra2-D and gra3-D) were submitted to ATH1 array hybridization.