showing 6 related works from this author
Regulation of Nicotiana tabacum osmotic stress-activated protein kinase and its cellular partner GAPDH by nitric oxide in response to salinity
2010
Several studies focusing on elucidating the mechanism of NO (nitric oxide) signalling in plant cells have highlighted that its biological effects are partly mediated by protein kinases. The identity of these kinases and details of how NO modulates their activities, however, remain poorly investigated. In the present study, we have attempted to clarify the mechanisms underlying NO action in the regulation of NtOSAK (Nicotiana tabacum osmotic stress-activated protein kinase), a member of the SNF1 (sucrose non-fermenting 1)-related protein kinase 2 family. We found that in tobacco BY-2 (bright-yellow 2) cells exposed to salt stress, NtOSAK is rapidly activated, partly through a NO-dependent pr…
Mechanisms of nitric-oxide-induced increase of free cytosolic Ca2+ concentration in Nicotiana plumbaginifolia cells.
2005
In this study, we investigated a role for nitric oxide (NO) in mediating the elevation of the free cytosolic Ca(2+) concentration ([Ca(2+)](cyt)) in plants using Nicotiana plumbaginifolia cells expressing the Ca(2+) reporter apoaequorin. Hyperosmotic stress induced a fast increase of [Ca(2+)](cyt) which was strongly reduced by pretreating cell suspensions with the NO scavenger carboxy PTIO, indicating that NO mediates [Ca(2+)](cyt) changes in plant cells challenged by abiotic stress. Accordingly, treatment of transgenic N. plumbaginifolia cells with the NO donor diethylamine NONOate was followed by a transient increase of [Ca(2+)](cyt) sensitive to plasma membrane Ca(2+) channel inhibitors …
Interplays between nitric oxide and reactive oxygen species in cryptogein signalling
2014
The cellular messenger nitric oxide (NO) has many functions in plants. In this study, we investigated its interplays with Reactive Oxygen Species (ROS) in the defense responses triggered by the elicitin cryptogein produced by the oomycete Phytophthora cryptogea. The production of NO induced by cryptogein in tobacco cell suspensions was partly regulated through a ROS-dependent pathway involving the NADPH oxidase NtRBOHD. In turn, NO down-regulated the level of H2O2 derived from NtRBOHD activity. Both NO and ROS synthesis appeared to be under the control of two redundant isoforms of histone deacetylases of type 2 acting as negative regulators of cell death. Occurrence of an interplay between …
Nitric oxide signalling in plants: interplays with Ca2+ and protein kinase
2008
International audience; Much attention has been paid to nitric oxide (NO)research since its discovery as a physiological mediator of plant defence responses. In recent years, newer roles have been attributed to NO, ranging from root development to stomatal closure. The molecular mechanisms underlying NO action in plants are just begun to emerge. The currently available data illustrate that NO can directly influence the activity of target proteins through nitrosylation and has the capacity to act as a Ca2+-mobilizing intracellular messenger. The interplay between NO and Ca2+ has important functional implications, expanding and enriching the possibilities for modulating transduction processes…
Nitric oxide and glutathione impact the expression of iron uptake- and iron transport-related genes as well as the content of metals in A. thaliana p…
2012
International audience; Mounting evidence indicate that nitric oxide (NO) acts as a signaling molecule mediating iron deficiency responses through the upregulation of the expression of iron uptake-related genes. Accordingly, NO donors such as nitrosoglutathione (GSNO) were reported to improve the fitness of plants grown under iron deficiency. Here, we showed that glutathione, a by-product of GSNO, triggered the upregulation of the expression of iron uptake- and transport-related gene and an increase of iron concentration in Arabidopsis thaliana seedlings facing iron deficiency. Furthermore, we provided evidence that under iron deficiency, NO released by GSNO did not improve the root iron co…
Nitric Oxide in Plants: Production and Cross-talk with Ca2+ Signaling
2008
International audience; Nitric oxide (NO) is a diatomic gas that performs crucial functions in a wide array of physiological processes in animals. The past several years have revealed much about its roles in plants. It is well established that NO is synthesized from nitrite by nitrate reductase (NR) and via chemical pathways. There is increasing evidence for the occurrence of an alternative pathway in which NO production is catalysed from L-arginine by a so far non-identified enzyme. Contradictory results have been reported regarding the respective involvement of these enzymes in specific physiological conditions. Although much remains to be proved, we assume that these inconsistencies can …