Brecht Wybouw

Abstract During secondary growth, the vascular cambium produces conductive xylem and phloem cells, while the phellogen (cork cambium) deposits phellem (cork) as the outermost protective barrier. Although most of the secondary tissues are made up of parenchyma cells, which are also produced by both cambia, their diversity and function are poorly understood.

Contents Summary I. Introduction II. The molecular regulatory network in cambium development III. Changing the perception of stem cells in the cambium IV. Challenges in defining cambium stem cells V. Repositioning the molecular regulators in the cambium VI. Comparison of CLE peptide – WUS-family signalling in three meristems VII. Future prospective Acknowledgements References I.

Abstract Vascular cambium contains bifacial stem cells, which produce secondary xylem to one side and secondary phloem to the other. However, how these fate decisions are regulated is unknown. Here we show that the positioning of an auxin signalling maximum within the cambium determines the fate of stem cell daughters. The position is modulated by gibberellin-regulated, PIN1-dependent polar auxin transport.