The phytohormone auxin is a major regulator of diverse aspects of plant growth and development. The ubiquitin-ligase complex SCF (for Skp1-Cul1-F-box protein), which includes the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX (TIR1/AFB) auxin receptor family, has recently been demonstrated to be critical for auxin-mediated transcriptional regulation. Early-phase auxin-induced hypocotyl elo...

The phytohormone auxin is a major regulator of diverse aspects of plant growth and development. The ubiquitin-ligase complex SCF(TIR1/AFB) (for Skp1-Cul1-F-box protein), which includes the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX (TIR1/AFB) auxin receptor family, has recently been demonstrated to be critical for auxin-mediated transcriptional regulation. Early-phase auxin-induced hyp...

At high vegetation density, shade-intolerant plants sense a reduction in the red (660 nm) to far-red (730 nm) light ratio (R/FR) in addition to a general reduction in light intensity. These light signals trigger a spectrum of morphological changes manifested by growth of stem-like tissue (hypocotyl, petiole, etc.) instead of harvestable organs (leaves, fruits, seeds, etc.)-namely, shade avoidan...

Polar transport of the auxin indole-3-butyric acid (IBA) has recently been shown to occur in Arabidopsis (Arabidopis thaliana) seedlings, yet the physiological importance of this process has yet to be fully resolved. Here we describe the first demonstration of altered IBA transport in an Arabidopsis mutant, and show that the resistant to IBA (rib1) mutation results in alterations in growth, dev...

A fundamental feature of development in multicellular organisms is the specification and patterning of distinct cell types. An important issue in cell specification relates to the developmental origin of the mechanisms that establish celltype patterns. Of particular interest is the relationship between the origin of cell patterning mechanisms and the development of the anatomy and identity of t...

Aim. Improving methods for increasing the efficiency of obtaining callus cultures and somaclones flax (Linum usitatissimum L.) in vitro. Methods. Hypocotyl segments were cultured on Murashige Skoog nutrient medium supplemented with sucrose (30 g/l) phytohormones at various concentrations. Other conditions: photoperiod 16 hours, illuminance 2500 lx, relative humidity 60–80%, air temperature 22–2...