Endogenous auxin biosynthesis and de novo root organogenesis

A seed high-lysine trait is negatively associated with the TCA cycle and slows down Arabidopsis seed germination. Malvar TM. 2008. Modifying lysine biosynthesis and catabolism in corn with a single bifunctional expression/silencing transgene cassette. 1995. The lysine-dependent stimulation of lysine catabolism in tobacco seed requires calcium and protein-phosphorylation. Expression of de novo high-lysine alpha-helical coiled-coil proteins may significantly increase the accumulated levels of lysine in mature seeds of transgenic tobacco plants. Concerted regulation of lysine and threonine synthesis in tobacco plants expressing bacterial feedback-insensitive aspartate kinase and dihydrodipicolinate synthase. Mutant gene that changes protein composition and increases lysine content of maize endosperm. Increased lysine synthesis coupled with a knockout of its catabolism synergistically boosts lysine content and also transregulates the metabolism of other amino acids in Arabidopsis seeds. Lysine metabolism is concurrently regulated by synthesis and catabolism in both reproductive and vegetative tissues. Induction of adventitious roots is essential for vegetative propagation of plants, and auxin has long been used as an exogenous root-inducing agent. In this issue of Journal of Experimental Botany, Chen et al. (pages 4273–4284) demonstrate that different members of the YUCCA family orchestrate the endogenous auxin biosynthesis that is required for the induction of adventitious roots. Sun Wukong, also known as the Monkey King, is the main character in the classical Chinese novel Journey to the West. As a fabled deity, he was endowed with magical properties allowing each of his hairs to be transformed into clones of himself as needed. Plants also possess the remarkable ability of multiplication , with detached pieces of adult tissues capable of forming an entire plant body (Gordon et al. This unique ability is mainly based on de novo organogenesis, in which adventitious shoots or roots are generated from isolated tissues or organs De novo organogenesis can be induced under both natural and tissue culture conditions (Chen et al., 2014). Plant organs, such as stems and leaves, give rise to adventitious roots under natural growth conditions and this property has long been used for vegetative propagation of elite genotypes in agriculture, forestry and horticulture (De Klerk et al., 1999). Six decades ago, Skoog and Miller demonstrated that the entire plant could be regenerated by tissue culture (Skoog and Miller, 1957). They showed that culturing explants in medium containing high levels of cytokinin induced the formation of adventitious shoots, whereas medium with high levels of auxin triggered initiation of adventitious roots. …