Mutual interactions of the phytohormones, cytokinins and auxin determine root or shoot identity during postembryonic organogenesis in plants. However, our understanding of the role of hormonal metabolism and perception during early stages of cell fate reprogramming is still elusive. Here we show that auxin activates root formation, whereas cytokinins mediate early loss of the root identity, primordia disorganisation and initiation of shoot development. Exogenous and endogenous cytokinins influence the initiation of newly formed organs, as well as the pace of organ development. The process of shoot apical meristem establishment is accompanied by accumulation of endogenous cytokinins, differential regulation of genes for individual cytokinin receptors, strong activation of AHK4-mediated signalling and induction of the shoot-specific homeodomain regulator The last is associated with upregulation of isopentenyladenine-type cytokinins, revealing higher shoot-forming potential when compared with-zeatin. Moreover, AHK4-controlled cytokinin signalling negatively regulates the root stem cell organiser in the root quiescent centre. We propose an important role for endogenous cytokinin biosynthesis and AHK4-mediated cytokinin signalling in the control of-induced organ identity.

Summary The international human rights system became massive and often difficult to understand even for lawyers themselves. Do we really need different human rights organisations operating both worldwide and locally, dozens of human rights treaties and monitoring bodies? The present paper focuses on the relation between the UN Universal Periodic Review (UPR) and the Special Procedures of the Human Rights Council (SP), two mechanisms that may, at the first sight seem largely overlapping in their purpose and, yet, pulling in opposite directions, causing more confusion than bringing benefits. I assert that despite the thematic and jurisdictional overlap of the mechanisms, the UPR and the SP are largely complementary and the existence of both necessary..

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Příspěvek pojednává o institutu výživného určeného k tvorbě úspor, jeho smyslu a účelovém určení takto naspořených částek. Autoři se zamýšlí nad úskalími spojenými se současnou úpravou správy takto naspořených částech. Příspěvek představuje institut svěřenského fondu jakožto flexibilní nástroj vhodný pro efektivní správu majetku. Demonstruje jaké výhody by mohla přinést možnost využití svěřenského fondu pro správu výživného určeného k tvorbě úspor.