ABI1, a protein phosphatase 2C, is a key component of signal transduction in Arabidopsis. It regulates diverse responses to the phytohormone abscisic acid (ABA) such as stomatal closure, seed dormancy and inhibition of vegetative growth. By analysing proteins capable of interacting with ABI1, we have identified the homeodomain protein ATHB6 as a regulator of the ABA signal pathway.
View Article and Find Full Text PDFSustainable development is the only kind of development possible for help in the third world. Due to various historical, political, geographic and climatic conditions the divergence between those countries providing and those receiving help is so vast that donations of labor and/or money is simply not enough. Rather, communities have to be taught to support and develop themselves during the receipt of aid and especially after the help pulls out.
View Article and Find Full Text PDFEnteroviruses of the Picornaviridae and primarily coxsackieviruses of group B (CVB) can be detected in humans and various experimental murine models of acute myocarditis and chronic heart muscle diseases indicating enterovirus persistence in the myocardium. Persistent myocardial infection is characterized by restricted viral replication and gene expression in myocytes capable of sustaining chronic inflammation. Viral cytotoxicity was found to be crucial for organ pathology both during acute and persistent infection.
View Article and Find Full Text PDFColl Antropol
June 1999
The methods and theories of science are in a state of constant flux. With the perimeters of science changing so does the subject of inquiry. Ethnology, a relatively young science underwent a drastic change at the turn of the century as unillineal evolutionism of the preceding century became obsolete and gave away to diffusionism.
View Article and Find Full Text PDFThe regulation of intracellular ion concentrations is a fundamental property of living cells. Although many ion transporters have been identified, the systems that modulate their activity remain largely unknown. We have characterized two partially redundant genes from Saccharomyces cerevisiae, HAL4/SAT4 and HAL5, that encode homologous protein kinases implicated in the regulation of cation uptake.
View Article and Find Full Text PDFInositol monophosphatases (IMPases) are lithium-sensitive enzymes that participate in the inositol cycle of calcium signalling and in inositol biosynthesis. Two open reading frames (YHR046c and YDR287w) with homology to animal and plant IMPases are present in the yeast genome. The two recombinant purified proteins were shown to catalyse inositol-1-phosphate hydrolysis sensitive to lithium and sodium.
View Article and Find Full Text PDFWe report the cloning of both the cDNA and the corresponding genomic sequence of a new PP2C from Arabidopsis thaliana, named AtP2C-HA (for homology to ABI1/ABI2). The AtP2C-HA cDNA contains an open reading frame of 1536 bp and encodes a putative protein of 511 amino acids with a predicted molecular mass of 55.7 kDa.
View Article and Find Full Text PDFThe plant hormone abscisic acid (ABA) mediates various responses such as stomatal closure, maintenance of seed dormancy, and inhibition of plant growth. All three responses are regulated by the ABI1 gene product. The ABI1 protein (ABI1p) has been characterized as a protein serine/threonine phosphatase of type 2C that is highly affected in its activity by changes in the proton and magnesium ion concentrations.
View Article and Find Full Text PDFThe plant hormone abscisic acid (ABA) mediates various responses such as stomatal closure, the maintenance of seed dormancy, and the inhibition of plant growth. All three responses are affected in the ABA-insensitive mutant abi1 of Arabidopsis thaliana, suggesting that an early step in the signaling of ABA is controlled by the ABI1 locus. The ABI1 gene was cloned by chromosome walking, and a missense mutation was identified in the structural gene of the abi1 mutant.
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