From central-peripheral to adaxial-abaxial.

Higher plants are constructed of three organs--the stem, the root and the leaf. The stem and the root have two axes, apical-basal and central-peripheral, which cross orthogonally. Leaves develop from the shoot apical meristem as lateral organs that have three different axes, apical-basal, adaxial-abaxial and right-left.

Galphaq-dependent activation of mitogen-activated protein kinase kinase 4/c-Jun N-terminal kinase cascade.

G-protein-coupled receptors (GPCRs) typically activate c-Jun N-terminal kinase (JNK) through the G protein betagamma subunit (Gbetagamma), in a manner dependent on Rho family small GTPases, in mammalian cells. Here we show that JNK activation by the prototypic Gq-coupled alpha1B-adrenergic receptor is mediated by the alpha subunit of Gq (Galphaq), not by Gbetagamma, using a transient transfection system in human embryonic kidney cells. JNK activation by the alpha1B-adrenergic receptor/Galphaq was selectively mediated by mitogen-activated protein kinase kinase 4 (MKK4), but not MKK7.

Biosynthetic Relationship between Acutumine and Dechloroacutumine in Menispermum dauricum Root Cultures.

The biosynthetic relationship between acutumine 1 and dechloroacutumine 2 was studied using (13)C-labeled tyrosine and (3)H-labeled 2 as tracers. (13)C-NMR spectra of (13)C-labeled 1 and 2 showed that the alkaloids, each composed of two molecules of tyrosine, are derived from the same biosynthetic pathway. Feeding Menispermum dauricum (Menispermaceae) roots, cultured in a chloride-enriched medium, with (3)H-labeled 2 demonstrated that 1 is the only alkaloid metabolite of 2.

Constitutive expression of the neutral PR-5 (OLP, PR-5d) gene in roots and cultured cells of tobacco is mediated by ethylene-responsive cis-element AGCCGCC sequences.

The constitutive accumulation of tobacco neutral PR-5 (osmotin-like protein; OLP, PR-5d) in roots and cultured cells was studied in transgenic tobacco plants harboring the OLP promoter::GUS gene. This construct showed strong β-glucuronidase expression in vascular tissues and cortex of roots as well as in cultured cells. Analysis using a mutated promoter showed that ethylene-responsive elements (AGCCGCC) were necessary for constitutive expression in roots and cultured cells.

Construction of gene expression system in cultured tobacco cells.

To construct a gene expression system in cultured tobacco cells, useful regulatory elements of plant genes were studied. The promoter of the horseradish peroxidase gene, prxC2, showed high activity in tobacco cells, and it contained enhancer sequences and a cis element for wound induction. The heat shock promoter of the HSP18.