Phototropins, plant blue light receptors, mediate stomatal opening through the activation of the plasma membrane H(+)-ATPase by unknown mechanisms. Here we report that type 1 protein phosphatase (PP1) positively regulates the blue light signaling between phototropins and the H(+)-ATPase in guard cells of Vicia faba. We cloned the four catalytic subunits of PP1 (PP1c) from guard cells and determ...

A highly sensitive, solid-phase, enzyme-amplified immunoassay for the plant growth regulator (+)-abscisic acid (ABA) was developed. The assay sensitivity (0.2-10 fmol) was sufficient for analyzing free ABA in homogeneous tissue samples dissected from Vicia faba L. leaves. Eight hours after detached leaves had been desiccated to 10% loss of fresh weight, the bulk leaf ABA content increased from ...

Cytosolic calcium increases were analyzed in guard cells of the Arabidopsis farnesyltransferase deletion mutant era1-2 (enhanced response to abscisic acid). At low abscisic acid (ABA) concentrations (0.1 microM), increases of guard cell cytosolic calcium and stomatal closure were activated to a greater extent in the era1-2 mutant compared with the wild type. Patch clamping of era1-2 guard cells...

A micro-advancer device that positions a narrow-gauge needle within the vitreous humor of the rat eye is described. The device is compact, simple and inexpensive to manufacture. It consists of an outer guard needle and an inner injection needle that is advanced through the guard needle. With the rat held in a stereotaxic holder and the globe fixed to a stabilizing ring, the outer 25-gauge guard...

It has long been accepted that differential radial thickening of guard cells plays an important role in the turgor-driven shape changes required for stomatal pore opening to occur [1-4]. This textbook description derives from an original interpretation of structure rather than measurement of mechanical properties. Here we show, using atomic force microscopy, that although mature guard cells dis...

Guard cells are specialized cells located at the leaf surface delimiting pores which control gas exchanges between the plant and the atmosphere. To optimize the CO2 uptake necessary for photosynthesis while minimizing water loss, guard cells integrate environmental signals to adjust stomatal aperture. The size of the stomatal pore is regulated by movements of the guard cells driven by variation...

The guard zone computation problem claims utmost importance in VLSI layout design, where the circuit components (or the functional units/modules or groups/blocks of different sub-circuits) that may be viewed as a set of polygonal regions on a two-dimensional plane, are not supposed to be placed much closer to each other in order to avoid electrical (parasitic) effects among them. Each (group of...

oral cancer is considered a great threat to public health. tongue cancer accounts for nearly 30% of all oral cancers and usually seen in 50 to 60 year old men. oropharyngeal cancers account for 3% of all cancers in iran; as reported in 2003. the present study was designed to assess the epidemiologic and clinicopathologic characteristics of tongue cancer patients in two tehran's referral univers...

One of the most common malformations of the tongue is fissured tongue, very often, is accompanied by geographic tongue; the etiopathogenesis of them is not known. The aim of study was to evaluate the prevalence of fungi in cases of fissured and geographic tongue, and to determine their species and susceptibility to selected antifungal drugs. The study included 104 patients with fissured and/or ...

Eight muscles invest the human tongue: four extrinsic muscles have external origins and insert into the tongue body and four intrinsic muscles originate and terminate within the tongue. Previously, we noted minimal activation of the genioglossus tongue muscle during impeded protrusion tasks (i.e., having subjects push the tongue against a force transducer), suggesting that other muscles play a ...