Cyclic AMP pathway activation and extracellular zinc induce rapid intracellular zinc mobilization in Candida albicans

LK was supported by Innovation Fund Denmark, DK (4019-00019B). Pcovery ApS received funding from Wellcome Trust, Research Councils, UK (100480/Z/12), Novo Seeds, DK and Boehringer Ingelheim Venture Fund, D. DW is supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (102549/Z/13/Z), the Medical Research Council and University of Aberdeen (MR/N006364/1) and received support from a Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology (097377/Z/11/Z). The funders had no part in study design, data collection and interpretation, or the decision to submit the work for publication.Peer reviewedPublisher PD

RIN4 Functions with Plasma Membrane H+-ATPases to Regulate Stomatal Apertures during Pathogen Attack

In plants, the protein Rin4 acts with the plasma membrane H+-ATPase to regulate pathogen entry and the innate immune response, in part, through the regulation of stomatal closure

Proton and calcium pumping P-type ATPases and their regulation of plant responses to the environment

Plant plasma membrane H(+)-ATPases and Ca(2+)-ATPases maintain low cytoplasmic concentrations of H(+) and Ca(2+), respectively, and are essential for plant growth and development. These low concentrations allow plasma membrane H(+)-ATPases to function as electrogenic voltage stats, and Ca(2+)-ATPases as “off” mechanisms in Ca(2+)-based signal transduction. Although these pumps are autoregulated by cytoplasmic concentrations of H(+) and Ca(2+), respectively, they are also subject to exquisite regulation in response to biotic and abiotic events in the environment. A common paradigm for both types of pumps is the presence of terminal regulatory (R) domains that function as autoinhibitors that can be neutralized by multiple means, including phosphorylation. A picture is emerging in which some of the phosphosites in these R domains appear to be highly, nearly constantly phosphorylated, whereas others seem to be subject to dynamic phosphorylation. Thus, some sites might function as major switches, whereas others might simply reduce activity. Here, we provide an overview of the relevant transport systems and discuss recent advances that address their relation to external stimuli and physiological adaptations

Analysis of peptide PSY1 responding transcripts in the two Arabidopsis plant lines: wild type and psy1r receptor mutant

BACKGROUND: Small-secreted peptides are emerging as important components in cell-cell communication during basic developmental stages of plant cell growth and development. Plant peptide containing sulfated tyrosine 1 (PSY1) has been reported to promote cell expansion and differentiation in the elongation zone of roots. PSY1 action is dependent on a receptor PSY1R that triggers a signaling cascade leading to cell elongation. However little is known about cellular functions and the components involved in PSY1-based signaling cascade. RESULTS: Differentially expressed genes were identified in a wild type plant line and in a psy1r receptor mutant line of Arabidopsis thaliana after treatment with PSY1. Seventy-seven genes were found to be responsive to the PSY1 peptide in wild type plants while 154 genes were responsive in the receptor mutant plants. PSY1 activates the transcripts of genes involved in cell wall modification. Gene enrichment analysis revealed that PSY1-responsive genes are involved in responses to stimuli, metabolic processes and biosynthetic processes. The significant enrichment terms of PSY1-responsive genes were higher in psy1r mutant plants compared to in wild type plants. Two parallel responses to PSY1 were identified, differing in their dependency on the PSY1R receptor. Promoter analysis of the differentially expressed genes identified a light regulatory motif in some of these. CONCLUSION: PSY1-responsive genes are involved in cellular functions and stimuli responses suggesting a crosstalk between developmental cues and environmental stimuli. Possibly, two parallel responses to PSY1 exist. A motif involved in light regulation was identified in the promoter region of the differentially expressed genes. Reduced hypocotyl growth was observed in etiolated receptor mutant seedlings. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi: 10.1186/1471-2164-15-441) contains supplementary material, which is available to authorized users

On a quest for stress tolerance genes : membrane transporters in sensing and adapting to hostile soils

Abiotic stresses such as salinity, drought, and flooding severely limit food and fibre production and result in penalties of in excess of US$100 billion per annum to the agricultural sector. Improved abiotic stress tolerance to these environmental constraints via traditional or molecular breeding practices requires a good understanding of the physiological and molecular mechanisms behind roots sensing of hostile soils, as well as downstream signalling cascades to effectors mediating plant adaptive responses to the environment. In this review, we discuss some common mechanisms conferring plant tolerance to these three major abiotic stresses. Central to our discussion are: (i) the essentiality of membrane potential maintenance and ATP production/availability and its use for metabolic versus adaptive responses; (ii) reactive oxygen species and Ca2+ ‘signatures’ mediating stress signalling; and (iii) cytosolic K+ as the common denominator of plant adaptive responses. We discuss in detail how key plasma membrane and tonoplast transporters are regulated by various signalling molecules and processes observed in plants under stress conditions (e.g. changes in membrane potential; cytosolic pH and Ca2+; reactive oxygen species; polyamines; abscisic acid) and how these stress-induced changes are related to expression and activity of specific ion transporters. The reported results are then discussed in the context of strategies for breeding crops with improved abiotic stress tolerance. We also discuss a classical trade-off between tolerance and yield, and possible avenues for resolving this dilemma