Table of Contents
Cover image

Land plants show specific developmental processes, many of which are connected to the presence of semi-rigid cell walls. Reflecting this, the highly dynamic cytoskeleton of plant cells steadily reorganizes during all stages of a plant cell life and governs orientation of both cell division and expansion through unique structures like the preprophase band of microtubules (PPB) or phragmoplast. Camilleri et al. (pages 833–845) show that in the TONNEAU2 mutant plants, severe morphological alterations are noted in every organ, although all organs and cell types are present at their correct relative positions. The cover picture shows flowers of a weak allele of the TON2 mutation at different stages of development. In loss of function alleles, highly disorganized flowers are observed. Mutant cells show strong disorganization of the microtubule cytoskeleton and a complete absence of PPB before mitosis. The TON2 mutation affects a gene encoding a 2A-phosphatase subunit, which is likely involved in the phosphorylation control of key cytoskeletal elements.