Cell division pattern influences gene expression in the shoot apical meristem

The shoot apical meristem of angiosperms shows a highly conserved cellular architecture in which a change of cell division orientation correlates with early events of leaf initiation. However, the causal role of this altered cellular parameter in leaf formation is debatable. We have used the dynamin-like protein phragmoplastin as a tool to modify the pattern of cell division within the apical meristem. Taking a microinduction approach, we show that local alteration in cell division orientation is not sufficient to induce morphogenesis in the meristem. Surprisingly, an altered cell division pattern did lead to an altered pattern of expression of genes implicated in aspects of leaf formation. Our data identify inducible expression of phragmoplastin as a tool to manipulate cell division pattern. Furthermore, they indicate that a mechanism exists by which cells in the meristem can respond at the level of gene expression to altered parameters of cell division. These data are discussed in the context of a model linking leaf morphogenesis and differentiation

Whose preferences count?

An important consideration when choosing how to allocate health care resources is the improvements in patients' health-related quality of life (HRQoL) that alternative allocations generate. There is considerable debate about whose preferences should be used when measuring and valuing HRQoL. This debate has usually been in terms of whether the values of patients or the general public are the most appropriate. It is argued in this paper that this is a false dichotomy that does not facilitate understanding of empirical evidence. Nor, more importantly, does it address one of the most important issues in the debate about whose preferences count, that is, whether the fact that many people adapt to poor health states should be taken into account when ascribing values to those states. A conceptual framework is developed to facilitate a more fruitful discussion of the issues relating to the question of whose preferences should count