The plasma membrane H(+)-ATPase builds up a pH and potential gradient across the plasma membrane, thus activating a series of secondary ion and metabolite transporters. pma4 (for plasma membrane H(+)-ATPase 4), the most widely expressed H(+)-ATPase isogene in Nicotiana plumbaginifolia, was overexpressed in tobacco. Plants that overexpressed PMA4 showed no major changes in plant growth under nor...

Late-flowering ecotypes and mutants of Arabidopsis thaliana and the related crucifer Thlaspi arvense flower early after cold treatment (vernalization). Treatment with the DNA demethylating agent 5-azacytidine induced nonvernalized plants to flower significantly earlier than untreated controls. Cytidine at similar concentrations had no effect on time to flower. In contrast, late-flowering mutant...

Higher plant nitrate reductases (NRs) carry an N-terminal domain whose sequence is not conserved in NRs from other organisms. A gene composed of a full-length tobacco NR cDNA with an internal deletion of 168 bp in the 5' end fused to the cauliflower mosaic virus 35S promoter and appropriate termination signals was constructed and designated as delta NR. An NR-deficient mutant of Nicotiana plumb...

The plasma membrane H 1 -ATPase builds up a pH and potential gradient across the plasma membrane, thus activating a series of secondary ion and metabolite transporters. pma4 (for plasma membrane H 1 -ATPase 4), the most widely expressed H 1 -ATPase isogene in Nicotiana plumbaginifolia , was overexpressed in tobacco. Plants that overexpressed PMA4 showed no major changes in plant growth under no...

Cold shock elicits an immediate rise in cytosolic free calcium concentration ([Ca2+]cyt) in both chilling-resistant Arabidopsis and chilling-sensitive tobacco (Nicotiana plumbaginifolia). In Arabidopsis, lanthanum or EGTA caused a partial inhibition of both cold shock [Ca2+]cyt elevation and cold-dependent kin1 gene expression. This suggested that calcium influx plays a major role in the cold s...

A nodule nuclear factor, NAT2, interacts with two AT-rich binding sites (NAT2 BS1 and NAT2 BS2) in the soybean leghemoglobin (lb) c3 promoter. In transgenic Lotus corniculatus nodules, an oligonucleotide containing NAT2 BS1 activated an inactive -159 lbc3 promoter when placed immediately upstream of the promoter. The activation was independent of the orientation of NAT2 BS1 but was dependent on...

In the Solanaceae, biotic and abiotic elicitors induce de novo synthesis of sesquiterpenoid stress metabolites known as phytoalexins. Because plant hormones play critical roles in the induction of defense-responsive genes, we have explored the effect of abscisic acid (ABA) on the synthesis of capsidiol, the major wild tobacco (Nicotiana plumbaginifolia) sesquiterpenoid phytoalexin, using wild-t...

Glutathione S-transferases (4) are involved in numerous plant physiological processes such as herbicide resistance (8), senescing flower petal response to ethylene (7), host response to pathogenic attack (2), and mammalian systems in the detoxification of xenobiotics. It has also been proposed that human glutathione S-transferase interacts with mercury, copper, and cadmium, therefore becoming a...