Elevations in cytoplasmic calcium ([Ca(2)+](cyt)) are an important component of early abscisic acid (ABA) signal transduction. To determine whether defined mutations in ABA signal transduction affect [Ca(2)+](cyt) signaling, the Ca(2)+-sensitive fluorescent dye fura 2 was loaded into the cytoplasm of Arabidopsis guard cells. Oscillations in [Ca(2)+](cyt) could be induced when the external calci...

The Neurospora crassa CYT-18 protein, the mitochondrial tyrosyl-tRNA synthetase, functions in splicing group I introns by inducing formation of the catalytically active RNA structure. Here, we identified a DEAD-box protein (CYT-19) that functions in concert with CYT-18 to promote group I intron splicing in vivo and vitro. CYT-19 does not bind specifically to group I intron RNAs and instead func...

We have tested the hypothesis that circadian oscillations in the concentration of cytosolic free calcium ([Ca2+]cyt) can encode information. We imaged oscillations of [Ca2+]cyt in the cotyledons and leaves of Arabidopsis (Arabidopsis thaliana) that have a 24-h period in light/dark cycles and also constant light. The amplitude, phase, and shape of the oscillations of [Ca2+]cyt and [Ca2+]cyt at c...

Cytochrome b561 (Cyt-b561) proteins are important for plant growth, development, and prevention of damage to plants. Because of their high sequence divergence, thorough mining of Cyt-b561 proteins from plant genomes are not easy. Currently there is only one Cyt-b561 gene found in the maize and none in the soybean genome. However, 22 have been identified in the Arabidopsis thaliana genome. We te...

In Rhodobacter sphaeroides chromatophores, cytochromes (cyt) c(1) and c(2) have closely overlapping spectra, and their spectral deconvolution provides a challenging task. As a result, analyses of the kinetics of different cytochrome components of the bc(1) complex in purple bacteria usually report only the sum cyt c(1) + cyt c(2) kinetics. Here we used newly determined difference spectra of ind...

We found that cyt c Y67H and Y67R variants represent a state which resembles the conformational intermediate state in cyt c with high peroxidase activity; and also the hydrogen bond network around Tyr67 is associated with the conformational transition of cyt c; these suggest that the hydrogen bond network around Tyr67 is essential in maintaining the cyt c functioning not only as an electron tra...

in the cytoplasm ([Ca 2 1 ] cyt ) were interpreted as representing changes in [Ca 2 1 ] cyt –sensitive exocytosis and endocytosis. A continuous increase in [Ca 2 1 ] cyt resulted in a sigmoidal increase in C m values with a half-maximal concentration at z 1 m M. The steep increase in C m values was followed by a variable slow phase in changing C m values. When [Ca 2 1 ] cyt increased at a rate ...

BACKGROUND Cytisine (CYT), the most commonly used drug for smoking cessation in Poland, was experimentally found to induce convulsions. There is a lack of studies on the influence of CYT on the anticonvulsant activity of antiepileptic drugs (AEDs). METHODS The effects of CYT on the anticonvulsant activity of six AEDs were examined in maximal electroshock (MES)-induced seizures in mice. RESU...

Cytisine (CYT), one of the principal bioactive components derived from the seeds of Cytisus laborinum L, has been widely used for central nervous system (CNS) diseases treatment. The present study investigated the protective effect of CYT on cultured cortical neural injury induced by N-methyl-d-aspartate (NMDA). Our data showed that CYT conferred protective effect against loss of cellular viabi...

The 4S cytochrome c (Cyt c) reductase activity of several plant species was markedly stimulated by cyanide and ferrocyanide but those of the 8S nitrate reductase component and other particulate components of the maize (Zea mays L.) scutellum by comparison, were increased only slightly. The effect of cyanide and ferrocyanide was not due to elimination of cytochrome oxidase interference but resul...