Abstract
Myrosin cells in Capparales plants are idioblasts that accumulate myrosinase, which hydrolyzes glucosinolates to produce toxic compounds for repelling pests. We previously showed that Arabidopsis atvam3 mutants have abnormally larger number of myrosin cells. Myrosin cells are scattered along leaf veins in wild-type leaves, whereas they develop a network throughout the leaves in the mutants (1). To elucidate how myrosin cells differentiate, we analyzed atvam3 mutants. We found that atvam3 leaves have the distinguishably immature higher-order veins and abnormally discontinuous second-order veins. DNA microarray analysis revealed that young atvam3 leaves down-regulated a significant number of genes that include the genes related to biosynthesis and transport of phytohormones and the genes response to phytohormones. We discuss about the involvement of phytohormones in the differentiation of myrosin cells of the leaves.
(1)Ueda et al. (2006) Plant Cell Physiol., 47,164-175
