Inhibition of photosynthetic activities under slow water stress measured in vivo by the photoacoustic method

Fifteen species of Melaleuca and two species of Callistemon from the field were examined to determine whether they accumulated nitrogen-containing compatible solutes and, if so, which. In addition to L-proline, N-methyl-L-proline (MP) (isolated for the first time from plants), trans-4-hydroxy-N-methyl- L-proline (MHP), and N, N'-dimethyl-trans-4-hydroxy-L-proline (DHP) were found in various combinations in the 15 Melaleuca species. M. lanceolata seedlings were subjected to water or salinity stress and M. uncinata to water stress under laboratory conditions. In both species significant reductions in leaf water potential (Ψw), osmotic potential (Ψs), turgor potential (Ψp), and relative water content (RWC) were observed in response to water stress. Salinised M. lanceolata plants showed considerable osmotic adjustment and maintained Ψp comparable to that of control plants; salinity, however, decreased RWC. In response to the imposed stresses under laboratory conditions, proline and MHP levels in M. lanceolata, and MHP and DHP levels in M. uncinata, increased. In addition to possible protective or osmotic roles in vivo, these proline analogues may be useful in chemotaxonomic investigations of Melaleuca species.

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Human in vivo percutaneous absorptiometry using the laser-photoacoustic method

Analytical Chemistry ◽

10.1021/ac00045a036 ◽

1992 ◽

Vol 64 (21) ◽

pp. 2661-2663 ◽

Cited By ~ 11

Author(s):

Ryuichi. Takamoto ◽

Ryujiro. Namba ◽

Masahiro. Matsuoka ◽

Tsuguo. Sawada

Keyword(s):

Photoacoustic Method

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Recombinant Water Stress Protein 1 (Re-WSP1) Suppresses Colon Cancer Cell Growth Through Mir-539/Β-Catenin Signaling Pathway

10.21203/rs.3.rs-302966/v1 ◽

2021 ◽

Author(s):

Songjia Guo ◽

Shuhua Shan ◽

Haili Wu ◽

huiqiang hao ◽

Zhuoyu Li

Keyword(s):

Colon Cancer ◽

Water Stress ◽

Cell Growth ◽

Molecular Mechanisms ◽

Stress Protein ◽

Pcr Analysis ◽

Dependent Manner ◽

Nostoc Commune

Abstract Nostoc commune Vauch is a nitrogen-fixing blue-green algae, contains a large number of active molecules with medicinal functions. Our previous study found that a water stress protein (WSP1) from Nostoc commune Vauch and its the recombinant protein (Re-WSP1) exhibited significant anti-colon cancer (CRC) activity both in vitro and in vivo. However, the underlying mechanism remains unknown. In this study, the CCK8 and clonogenic assays showed that Re-WSP1 restrained the colon cancer growth in a dose-dependent manner. Mechanistically, Re-WSP1 inhibited the expression of β-catenin, which was partly reversed by LiCl treatment, demonstrating a key role in Re-WSP1-induced inhibition of cell growth. Quantitative PCR analysis showed that the expression of microRNA-539 (miR-539) was significantly up-regulated upon Re-WSP1 treatment. Moreover, miR-539 negatively regulateed the expression of β-catenin through directly binds to the 3’UTR of β-catenin mRNA. Taken together, our data demonstrate that Re-WSP1 suppresses the CRC growth via miR-539/β-catenin axis, which provides new insights into the molecular mechanisms underlying Re-WSP1 against CRC.

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Effect of Water Stress on Reproduction and Colonization of Podosphaera aphanis of Strawberry

Plant Disease ◽

10.1094/pdis-10-19-2172-re ◽

2020 ◽

Vol 104 (11) ◽

pp. 2973-2978

Author(s):

Franca G. Rossi ◽

Belachew Asalf ◽

Chloe Grieu ◽

Rodrigo B. Onofre ◽

Natalia A. Peres ◽

...

Keyword(s):

Water Stress ◽

Powdery Mildew ◽

Plant Stress ◽

Leaf Curling ◽

In Vivo Experiments ◽

Powdery Mildews ◽

Leaf Surfaces ◽

Mild Water Stress

In a number of pathosystems involving the powdery mildews (Erysiphales), plant stress is associated with decreased disease susceptibility and is detrimental to pathogen growth and reproduction. However, in strawberry, anecdotal observations associate severe powdery mildew (Podosphaera aphanis) with water stress. In a 2017 survey of 42 strawberry growers in Norway and California, 40 growers agreed with a statement that water-stressed strawberry plants were more susceptible to powdery mildew compared with nonstressed plants. In repeated in vitro and in vivo experiments, we found that water stress was consistently and significantly unfavorable to conidial germination, infection, and increases in disease severity. Deleterious effects on the pathogen were observed from both preinoculation and postinoculation water stress in the host. Soil moisture content in the range from 0 to 50% was correlated (R2 = 0.897) with germinability of conidia harvested from extant colonies that developed on plants growing at different levels of water stress. These studies confirm that P. aphanis fits the norm for biotrophic powdery mildews and hosts under stress. Mild water stress, compared with a state of optimal hydration, is likely to decrease rather than increase susceptibility of strawberry to P. aphanis. We believe it is possible that foliar symptoms of leaf curling due to diffuse and inconspicuous infection of the lower leaf surfaces by P. aphanis could easily be mistakenly attributed to water stress, which we observed as having a nearly identical leaf curling symptom in strawberry.

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