This study describes functional characterization of two putative poplar PHOTOPERIOD RESPONSE 1 (PHOR1) orthologues. The expression and sequence analyses indicate that the two poplar genes diverged, at least partially, in function. PtPHOR1_1 is most highly expressed in roots and induced by short days, while PtPHOR1_2 is more uniformly expressed throughout plant tissues and is not responsive to s...

How do plants determine the number of dividing cells required to optimise root growth and ensure seedling establishment? The signals auxin, cytokinin and gibberellin control the balance between cell division and differentiation by regulating SHY2.

Vascular plants invariably contain a class II diterpene cyclase (EC 5.5.1.x), as an entcopalyl diphosphate synthase is required for gibberellin phytohormone biosynthesis. This has provided the basis for evolution of a functionally diverse enzymatic family. A bifunctional diterpene synthase was characterized from the lycophyte Selaginella moellendorffii. The structure of its product, labda-7,13E...

Homologation of 16-dehydropregnenolone acetate leads to excellent stereocontrolled synthesis of unnatural C (20R) aldehydes and through compound .

To elucidate the involvement of gibberellin (GA) in the growth regulation of Arabidopsis roots, effects of shoot-applied GA and GA-biosynthesis inhibitors on the root were examined. Applying GA to the shoot of Arabidopsis slightly enhanced the primary root elongation. Treating shoots with uniconazole, a GA biosynthesis inhibitor, also resulted in enhancement of primary root elongation, while sh...

Suspension cultures were incubated in the presence and absence of gibberellic acid (GA(3)) in an attempt to define a new experimental system for study of the molecular action of gibberellins upon growth. Unlike many suspension cultures, an auxin-independent green clone from spinach (Spinacia oleracea L.) and an auxin-dependent line of "Paul's Scarlet" rose (Rosa sp.) were promoted in expansion ...

Recent studies using biochemical and genetic approaches have identified a number of components, including several negative regulators, of the gibberellin (GA) signal transduction pathway in higher plants. The basal state of GA signaling is likely to be repressive, and the GA signal seems to activate the pathway by de-repression to allow GA-stimulated growth and development.

Recent molecular biological and genetical studies have identified several positive and negative regulators of gibberellin (GA) signalling pathways in higher plants. The DELLA protein functions as a negative regulator of GA signalling; its degradation through the ubiquitin/proteasome pathway is a key event in the regulation of GA-stimulated processes.