The "dead donor rule" is increasingly under attack for several reasons. First, there has long been disagreement about whether there is a correct or coherent definition of "death." Second, it has long been clear that the concept and ascertainment of "brain death" is medically flawed. Third, the requirement stands in the way of improving organ supply by prohibiting organ removal from patients who...

The historic developmental hourglass concept depicts the convergence of animal embryos to a common form during the phylotypic period. Recently, it has been shown that a transcriptomic hourglass is associated with this morphological pattern, consistent with the idea of underlying selective constraints due to intense molecular interactions during body plan establishment. Although plants do not ex...

The expression of invertases was analyzed in vegetative organs of well-watered and water-stressed maize (Zea mays) plants. Early changes in sucrose metabolism and in acid soluble invertase expression were observed in vegetative sink and source organs under mild water stress. The organ-specific induction of acid invertase activity was correlated with an increase in the Ivr2 gene transcripts and ...

Many plant cells can be reprogrammed into a pluripotent state that allows ectopic organ development. Inducing totipotent states to stimulate somatic embryo (SE) development is, however, challenging due to insufficient understanding of molecular barriers that prevent somatic cell dedifferentiation. Here we show that Polycomb repressive complex 2 (PRC2)-activity imposes a barrier to hormone-media...

GAMYB was first isolated as a positive transcriptional regulator of gibberellin (GA)-dependent alpha-amylase expression in barley aleurone cells, and its molecular and biochemical properties have been well characterized. However, the role of GAMYB elsewhere in the plant is not well understood. To investigate the molecular function of GAMYB outside of the aleurone cells, we isolated loss-of-func...

The phytohormone abscisic acid (ABA) regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and...

The EMBRYONIC FLOWER (EMF) genes EMF1 and EMF2 are required to maintain vegetative development and repress flower development. EMF1 encodes a putative transcriptional regulator, and EMF2 encodes a Polycomb group protein homolog. We examined expression profiles of emf mutants using GeneChip technology. The high degree of overlap in expression changes from the wild type among the emf1 and emf2 mu...

Climate change projections predict warmer and drier conditions. In general, moderate to severe water stress reduce plant vegetative growth and leaf photosynthesis. However, vegetative and reproductive growths show different sensitivities to water deficit. In fruit trees, water restrictions may have serious implications not only on tree growth and yield, but also on fruit quality, which might be...

Cymbidium faberi is a traditional orchid flower in China that is highly appreciated for its fragrant aroma from its zygomorphic flowers. One bottleneck of the commercial production of C. faberi is the long vegetative growth phase of the orchid and the difficulty of the regulation of its flowering time. Moreover, its flower size, shape and color are often targeting traits for orchid breeders. Un...