Phase separation of SGS3 drives siRNA body formation and promotes endogenous gene silencing.

The generation of small interfering RNA (siRNA) involves many RNA processing components, including SUPPRESSOR OF GENE SILENCING 3 (SGS3), RNA-DEPENDENT RNA POLYMERASE 6 (RDR6), and DICER-LIKE proteins (DCLs). Nonetheless, how these components are coordinated to produce siRNAs is unclear. Here, we show that SGS3 forms condensates via phase separation in vivo and in vitro. SGS3 interacts with RDR6 and drives it to form siRNA bodies in cytoplasm, which is promoted by SGS3-targeted RNAs. Disrupting SGS3 phase separation abrogates siRNA body assembly and siRNA biogenesis, whereas coexpression of SGS3 and RDR6 induces siRNA body formation in tobacco and yeast cells. Dysfunction in translation and mRNA decay increases the number of siRNA bodies, whereas DCL2/4 mutations enhance their size. Purification of SGS3 condensates identifies numerous RNA-binding proteins and siRNA processing components. Together, our findings reveal that SGS3 phase separation-mediated formation of siRNA bodies is essential for siRNA production and gene silencing.

Acupoints sensitization in people with and without chronic low back pain:A matched-sample cross-sectional study.

BACKGROUND: Acupoints are considered a dynamic functional area, which can reflect the internal condition of the body. In pathological states, disease-related acupoints are believed to be activated, which is known as acupoint sensitization. OBJECTIVE: This study aimed to investigate the major manifestations of acupoint sensitization in patients with chronic low back pain (cLBP) to provide better understanding of acupoint sensitization phenomena in the context of cLBP. METHODS: This study was a matched-sample cross-sectional study 16 participants diagnosed with cLBP and 16 healthy controls matched in age, sex, and ethnicity were included. The following aspects of sensitization phenomena of targeted points were compared: pressure pain threshold (PPT), skin temperature, surface electrical conductance, receptive field, and morphological change of skin. RESULTS: PPT at points of interest were significantly lower in cLBP participants compared with healthy controls (P< 0.05); in addition, receptive field was found to be larger at left BL 23 in cLBP participants (P< 0.05). There was no statistically significant difference in skin temperature, electrical conductance, or morphology between the two groups. CONCLUSIONS: Reduced PPT at all detected points and enlarged receptive field at left BL 23 were found in cLBP participants. These two features appear key in defining acupoint sensitization in cLBP, and provide evidence for selecting and locating acupuncture points in future clinical studies.

Biocrust Research in China: Recent Progress and Application in Land Degradation Control.

Desert ecosystems are generally considered lifeless habitats characterised by extreme environmental conditions, yet they are successfully colonised by various biocrust nonvascular communities. A biocrust is not only an important ecosystem engineer and a bioindicator of desert ecological restoration but also plays a vital role in linking surficial abiotic and biotic factors. Thus, extensive research has been conducted on biocrusts in critical dryland zones. However, few studies have been conducted in the vast temperate deserts of China prior to the beginning of this century. We reviewed the research on biocrusts conducted in China since 2000, which firstly focused on the eco-physiological responses of biocrusts to species composition, abiotic stresses, and anthropological disturbances. Further, research on the spatial distributions of biocrusts as well as their succession at different spatial scales, and relationships with vascular plants and soil biomes (especially underlying mechanisms of seed retention, germination, establishment and survival of vascular plants during biocrust succession, and creation of suitable niches and food webs for soil animals and microorganisms) was analysed. Additionally, studies emphasising on the contribution of biocrusts to ecological and hydrological processes in deserts as well as their applications in the cultivation and inoculation of nonvascular plants for land degradation control and ecological restoration were assessed. Finally, recent research on biocrusts was evaluated to propose future emerging research themes and new frontiers.

The diversity of post-transcriptional gene silencing mediated by small silencing RNAs in plants.

In plants, post-transcriptional gene silencing (PTGS) tightly regulates development, maintains genome stability and protects plant against foreign genes. PTGS can be triggered by virus infection, transgene, and endogenous transcript, thus commonly serves as an RNA-based immune mechanism. Accordingly, based on the initiating factors, PTGS can be divided into viral-PTGS, transgene-PTGS, and endo-gene-PTGS. Unlike the intensely expressed invading transgenes and viral genes that frequently undergo PTGS, most endogenous genes do not trigger PTGS, except for a few that can produce endogenous small RNAs (sRNAs), including microRNA (miRNA) and small interfering RNA (siRNA). Different lengths of miRNA and siRNA, mainly 21-, 22- or 24-nucleotides (nt) exert diverse functions, ranging from target mRNA degradation, translational inhibition, or DNA methylation and chromatin modifications. The abundant 21-nt miRNA or siRNA, processed by RNase-III enzyme DICER-LIKE 1 (DCL1) and DCL4, respectively, have been well studied in the PTGS pathways. By contrast, the scarceness of endogenous 22-nt sRNAs that are primarily processed by DCL2 limits their research, although a few encouraging studies have been reported recently. Therefore, we review here our current understanding of diverse PTGS pathways triggered by a variety of sRNAs and summarize the distinct features of the 22-nt sRNA mediated PTGS.

Brassinosteroid-Activated BRI1-EMS-SUPPRESSOR 1 Inhibits Flavonoid Biosynthesis and Coordinates Growth and UV-B Stress Responses in Plants.

UV-B light is a potential stress factor in plants, but how plants coordinate growth and UV-B stress responses is not well understood. Here, we report that brassinosteroid (BR) signaling inhibits UV-B stress responses in Arabidopsis (Arabidopsis thaliana) and various crops by controlling flavonol biosynthesis. We further demonstrate that BRI1-EMS-SUPPRESSOR 1 (BES1) mediates the tradeoff between plant growth and UV-B defense responses. BES1, a master transcription factor involved in BR signaling, represses the expression of transcription factor genes MYB11, MYB12, and MYB111, which activate flavonol biosynthesis. BES1 directly binds to the promoters of these MYBs in a BR-enhanced manner to repress their expression, thereby reducing flavonol accumulation. However, exposure to broadband UV-B down-regulates BES1 expression, thus promoting flavonol accumulation. These findings demonstrate that BR-activated BES1 not only promotes growth but also inhibits flavonoid biosynthesis. UV-B stress suppresses the expression of BES1 to allocate energy to flavonoid biosynthesis and UV-B stress responses, allowing plants to switch from growth to UV-B stress responses in a timely manner.

The effectiveness of tai chi in breast cancer patients: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: Tai chi has been suggested as a potential effective intervention for improving function and wellbeing in breast cancer patients. This systematic review evaluated the current evidence for the effectiveness of tai chi in patients with breast cancer. METHODS: Randomized Controlled Trials (RCTs) evaluating the effects of tai chi in breast cancer patients were identified through searches in OVID MEDLINE, AMED, EMBASE, CINAHL, Cochrane Central Register of Controlled Trials, CNKI, VIP, and Wanfang Data, up to June 2019. Meta-analyses were performed for results syntheses. RESULTS: Sixteen RCTs involving 1268 participants were included in this review. It was demonstrated that tai chi is no different from conventional supportive care interventions in improving fatigue, sleeping quality, depression or body mass index at either 3 months or 6 months; however it significantly improves overall quality of life (QoL) at 3 months. Moreover, tai chi, when offered as an adjunct to conventional therapy, is more effective in improving fatigue at 3 months, and QoL at 3 months and 6 months compared to conventional therapy alone. CONCLUSION: Tai chi shows no improvement in fatigue compared with conventional supportive interventions, but it significantly relieves fatigue symptom for breast cancer patients when used with conventional supportive care interventions. Tai chi versus conventional supportive care interventions, and as an adjunct to conventional therapy is effective in improving QoL for breast cancer patients.

Understanding Acupoint Sensitization: A Narrative Review on Phenomena, Potential Mechanism, and Clinical Application.

As part of traditional Chinese medicine, acupoints are considered a dynamic functional area, which can reflect the internal condition of the body. When the body is suffering from disease or injury, corresponding acupoints are believed to be activated and manifest in several sensitized forms, including expansion of the receptive field, pain sensitization, and heat sensitization. Such phenomena are believed to gradually disappear concomitantly with recovery from the disease. Acupoint states are therefore changeable according to health status, a phenomenon known as acupoint sensitization. This review aims to provide an overview of acupoint sensitization based on existing research results and determine priorities for future research. Systematic literature retrieval was conducted in Medline, Embase, Cochrane Library, CINAHL, and AMED from inception to 18 July 2018. Current evidence from research findings to date indicate that acupoint sensitization is based on neurogenic inflammation and that stimulation of sensitized acupoints presents a potential trend of generating a better clinical effect when compared with stimulation of unsensitized points.

A Crucial Role of GA-Regulated Flavonol Biosynthesis in Root Growth of Arabidopsis.

Flavonols have been demonstrated to play many important roles in plant growth, development, and communication with other organisms. Flavonol biosynthesis is spatiotemporally regulated by the subgroup 7 R2R3-MYB (SG7 MYB) transcription factors including MYB11/MYB12/MYB111. However, whether SG7-MYB activity is subject to post-translational regulation remains unclear. Here, we show that gibberellic acid (GA) inhibits flavonol biosynthesis via DELLA proteins in Arabidopsis. Protein-protein interaction analyses revealed that DELLAs (RGA and GAI) interacted with SG7 MYBs (MYB12 and MYB111) both in vitro and in vivo, leading to enhanced affinity of MYB binding to the promoter regions of key genes for flavonol biosynthesis and thus increasing their transcriptional levels. We observed that the level of auxin in the root tip was negatively correlated with root flavonol content. Furthermore, genetic assays showed that loss-of-function mutations in MYB12, which is predominantly expressed in roots, partially rescued the short-root phenotype of the GA-deficient mutant ga1-3 by increasing root meristem size and mature cell size. Consistent with these observations, exogenous application of the flavonol quercetin restored the root meristem size of myb12 ga1-3 to that of ga1-3. Taken together, our data elucidate a molecular mechanism by which GA promotes root growth by directly reducing flavonol biosynthesis.

An ubiquitin-like protein SDE2 negatively affects sucrose-induced anthocyanin biosynthesis in Arabidopsis.

Anthocyanin biosynthesis is regulated by a conserved transcriptional MBW complex composed of MYB, bHLH and WD40 subunits. However, molecular mechanisms underlying transcriptional regulation of these MBW subunits remain largely elusive. In this study, we isolated an Arabidopsis mutant that displays a constitutive red color in aboveground tissues with retarded growth phenotypes. In the presence of sucrose, the mutant accumulates more than 3-fold anthocyanins of the wild type (WT), but cannot produce anthocyanins as WT in the absence of sucrose. Map-based cloning results demonstrated that the mutation occurs in the locus At4G01000, which encodes a conserved nuclear-localized ubiquitin-like (UBL) superfamily protein, silencing defective 2 (SDE2), in eukaryotes. SDE2 is ubiquitously expressed in various tissues. In the sucrose-induced anthocyanin biosynthesis, SDE2 expression was not responded to sucrose treatment at the early stage but was enhanced at the late stage. SDE2 mutations result in up-regulation of anthocyanin biosynthetic and regulatory genes. Yeast-two hybrid analysis indicated that SDE2 has no direct interaction with the MYB transcription factor PAP1 and bHLH factor TT8, indicating that SDE2 is a indirect factor to affect anthocyanin accumulation. Taking together, our data suggest that SDE2 may play a role in finely coordinating anthocyanin biosynthesis with other biological processes.

Arogenate Dehydratase Isoforms Differentially Regulate Anthocyanin Biosynthesis in Arabidopsis thaliana.

Anthocyanins, a group of L-phenylalanine (Phe)-derived flavonoids, have been demonstrated to play important roles in plant stress resistance and interactions between plants and insects. Although the anthocyanin biosynthetic pathway and its regulatory mechanisms have been extensively studied, it remains unclear whether the level of Phe supply affects anthocyanin biosynthesis. Here, we investigated the roles of arogenate dehydratases (ADTs), the key enzymes that catalyze the conversion of arogenate into Phe, in sucrose-induced anthocyanin biosynthesis in Arabidopsis. Genetic analysis showed that all six ADT isoforms function redundantly in anthocyanin biosynthesis but have differential contributions. ADT2 contributes the most to anthocyanin accumulation, followed by ADT1 and ADT3, and ADT4-ADT6. We found that anthocyanin content is positively correlated with the levels of Phe and sucrose-induced ADT transcripts in seedlings. Consistently, addition of Phe to the medium could dramatically increase anthocyanin content in the wild-type plants and rescue the phenotype of the adt1 adt3 double mutant regarding the anthocyanin accumulation. Moreover, transgenic plants overexpressing ADT4, which appears to be less sensitive to Phe than overexpression of ADT2, hyperaccumulate Phe and produce elevated level of anthocyanins. Taken together, our results suggest that the level of Phe is an important regulatory factor for sustaining anthocyanin biosynthesis.

Gross rainfall amount and maximum rainfall intensity in 60-minute influence on interception loss of shrubs: a 10-year observation in the Tengger Desert.

In water-limited regions, rainfall interception is influenced by rainfall properties and crown characteristics. Rainfall properties, aside from gross rainfall amount and duration (GR and RD), maximum rainfall intensity and rainless gap (RG), within rain events may heavily affect throughfall and interception by plants. From 2004 to 2014 (except for 2007), individual shrubs of Caragana korshinskii and Artemisia ordosica were selected to measure throughfall during 210 rain events. Various rainfall properties were auto-measured and crown characteristics, i.e., height, branch and leaf area index, crown area and volume of two shrubs were also measured. The relative interceptions of C. korshinskii and A. ordosica were 29.1% and 17.1%, respectively. Rainfall properties have more contributions than crown characteristics to throughfall and interception of shrubs. Throughfall and interception of shrubs can be explained by GR, RI60 (maximum rainfall intensities during 60 min), RD and RG in deceasing importance. However, relative throughfall and interception of two shrubs have different responses to rainfall properties and crown characteristics, those of C. korshinskii were closely related to rainfall properties, while those of A. ordosica were more dependent on crown characteristics. We highlight long-term monitoring is very necessary to determine the relationships between throughfall and interception with crown characteristics.

DELLA Proteins Promote Anthocyanin Biosynthesis via Sequestering MYBL2 and JAZ Suppressors of the MYB/bHLH/WD40 Complex in Arabidopsis thaliana.

Anthocyanin accumulation is recognized as a visible biomarker of plants that have suffered from environmental stresses. However, the molecular mechanisms underlying stress-induced anthocyanin biosynthesis remain unclear. Expression of anthocyanin-specific genes is regulated by the conserved MBW complex, which is composed of the MYB, bHLH, and WD40 subunits in higher plants. MBW activity is repressed by MYBL2 and the JAZ family proteins, which bind competitively to bHLH and MYB/bHLH, respectively. Here, we found that MYBL2 and JAZs mediate gibberellic acid-inhibited anthocyanin biosynthesis in Arabidopsis. Competitive pull-down and dual-luciferase assays showed that DELLA proteins directly sequester MYBL2 and JAZ repressors, leading to the release of bHLH/MYB subunits and subsequently to the formation of active MBW complex, which then activates the anthocyanin biosynthetic pathway. The JAZ-DELLA-MYBL2 module also plays an important role in abiotic stress-induced anthocyanin biosynthesis. Furthermore, we found that the DELLA protein RGA accumulates upon plant exposure to abiotic stresses. Altogether, our data reveal that DELLA-promoted anthocyanin biosynthesis is mediated at least in part by MYBL2 and JAZ regulatory proteins, providing new insights into the coordinated regulation of plant growth and defense through metabolic pathway regulation.

Auricular acupuncture with seed or pellet attachments for primary insomnia: a systematic review and meta-analysis.

BACKGROUND: Primary insomnia is a common health issue in the modern world. We conducted a systematic review of the auricular therapy, aiming to evaluate whether there are advantages of auricular acupuncture with seed or pellet attachments for the treatment of primary insomnia. METHODS: A search of relevant literatures was performed on major medical databases, including Medline, Embase, CENTRAL, CBM, CNKI, VIP, Wanfang Data and so on. Risk of bias evaluation, meta-analysis, sensitivity analysis and evidence rating of all extracted information were conducted also. RESULTS: A total of 1381 records were identified, with 15 studies deemed eligible for the present review. Meta-analyses were conducted in two comparisons separately: participants received auricular acupuncture were more likely to make an improvement in clinical effective rate (RR = 1.40, 95% CI 1.07 to 1.83), sleep duration (MD = 56.46, 95% CI 45.61 to 67.31), sleep efficiency(MD = 12.86, 95% CI 9.67 to 16.06), global score on PSQI (MD = -3.41, 95% CI -3.93 to -2.89), number of awakenings( MD = -3.27, 95% CI -6.30 to -0.25) and sleep onset latency(MD = -10.35, 95% CI -14.37 to -6.33) when compared to sham auricular acupuncture or placebo; while in auricular acupuncture VS medications comparison, a better effective rate (RR = 1.24, 95% CI 1.15 to 1.34), better sleep efficiency(MD = 21.44, 95% CI 16.30 to 26.58), lower PSQI score (MD = -3.62, 95% CI -4.59 to -2.65) and less adverse effect (RR = 0.11, 95% CI 0.04 to 0.26) can be seen also in auricular acupuncture group. Although these results suggested benefits of auricular acupuncture, the overall quality of evidence rated by the GRADE system was low. CONCLUSION: Statistical analyses of the outcomes revealed a positive effect of auricular acupuncture for primary insomnia. Nonetheless, considering the poor methodological quality, insufficient sample size and possible publication bias, current evidence is not yet adequate to provide a strong support for the use of auricular acupuncture in the treatment of primary insomnia. More strictly designed clinical studies will be needed to obtain a more explicit conclusion.

Nutrient levels within leaves, stems, and roots of the xeric species Reaumuria soongorica in relation to geographical, climatic, and soil conditions.

Besides water relations, nutrient allocation, and stoichiometric traits are fundamental feature of shrubs. Knowledge concerning the nutrient stoichiometry of xerophytes is essential to predicting the biogeochemical cycling in desert ecosystems as well as to understanding the homoeostasis and variability of nutrient traits in desert plants. Here, we focused on the temperate desert species Reaumuria soongorica and collected samples from plant organs and soil over 28 different locations that covered a wide distributional gradient of this species. Carbon (C), nitrogen (N), and phosphorus (P) concentrations and their stoichiometry were determined and subsequently compared with geographic, climatic, and edaphic factors. The mean leaf C, N, and P concentrations and C/N, C/P, and N/P ratios were 371.6 mg g(-1), 10.6 mg g(-1), 0.73 mg g(-1), and 59.7, 837.9, 15.7, respectively. Stem and root C concentrations were higher than leaf C, while leaf N was higher than stem and root N. Phosphorus concentration and N/P did not differ among plant organs. Significant differences were found between root C/N and leaf C/N as well as between root C/P and leaf C/P. Leaf nutrient traits respond to geographic and climatic factors, while nutrient concentrations of stems and roots are mostly affected by soil P and pH. We show that stoichiometric patterns in different plant organs had different responses to environmental variables. Studies of species-specific nutrient stoichiometry can help clarify plant-environment relationships and nutrient cycling patterns in desert ecosystems.

Leaf nitrogen and phosphorus of temperate desert plants in response to climate and soil nutrient availability.

In desert ecosystems, plant growth and nutrient uptake are restricted by availability of soil nitrogen (N) and phosphorus (P). The effects of both climate and soil nutrient conditions on N and P concentrations among desert plant life forms (annual, perennial and shrub) remain unclear. We assessed leaf N and P levels of 54 desert plants and measured the corresponding soil N and P in shallow (0-10 cm), middle (10-40 cm) and deep soil layers (40-100 cm), at 52 sites in a temperate desert of northwest China. Leaf P and N:P ratios varied markedly among life forms. Leaf P was higher in annuals and perennials than in shrubs. Leaf N and P showed a negative relationship with mean annual temperature (MAT) and no relationship with mean annual precipitation (MAP), but a positive relationship with soil P. Leaf P of shrubs was positively related to soil P in the deep soil. Our study indicated that leaf N and P across the three life forms were influenced by soil P. Deep-rooted plants may enhance the availability of P in the surface soil facilitating growth of shallow-rooted life forms in this N and P limited system, but further research is warranted on this aspect.

[Auricular acupuncture for primary insomnia: a systematic review based on GRADE system].

The clinical efficacy and safety of auricular acupuncture (AA) for treatment of primary insomnia was evaluated. After a comprehensive retrieval in domestic and foreign databases, literatures were strictly screened and Revman 5.2 software was applied to perform a Meta-analysis on eligible randomized controlled trials (RCTs). The evidence quality was assessed with GRADE profiler 3.6 software. As a result, 8 articles were included involving 894 patients. Compared among AA and sham AA, placebo AA, blank control, there was significant difference in Pittsburgh sleep quality index (PSQI) [WMD = -3.48, 95% CI (-3.96, -3.00)], sleep latency LWMD = -10.14, 95% CI (-17.16, -3.12)] and sleep awakening times [WMD = -9.98, 95% CI (-1.10,-0.48)]. Compared between AA and western medication, there was significant difference in PSQI [WMD = -3.62, 95% CI (-4.59, -2.65)]. The evidence quality was moderate in AA vs. sham AA, placebo AA or blank control, while that of the rest was extremely low. No reports of adverse events were described in all studies. In conclusion, for the treatment of primary insomnia, AA could effectively improve sleep quality, but due to the low evidence quality, cautious attitude should be taken on this conclusion, and clinical trials with large sample and high quality were needed in the further.

Ecological restoration and recovery in the wind-blown sand hazard areas of northern China: relationship between soil water and carrying capacity for vegetation in the Tengger Desert.

The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km(2) in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain. Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas. After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert, we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water. The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition. The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession. The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.

Responses of three different ecotypes of reed (Phragmites communis Trin.) to their natural habitats: leaf surface micro-morphology, anatomy, chloroplast ultrastructure and physio-chemical characteristics.

The adaptational characteristics due to long-term adaptation in the natural habitats of common reed (Phragmites communis Trin.) contrasted considerably among three different ecotypes: dune reed (DR), Gobi salt reed (GSR) and swamp reed (SR). The micromorphologies of leaf adaxial surfaces showed tapered setae and a non-smooth surface in DR, compound papillose structures with wax and hairs in GSR, but only papillose structures for the smooth surface of SR. Anatomical analysis showed that DR and GSR had higher bundle-sheath cell areas and a lower xylem/phloem ratio than SR. There were many sclerenchyma cells in vascular bundle of DR and GSR and crystal idioblasts in all ecotypes. Chloroplasts had ellipsoid shape in SR, but they were attached to the cell wall with oblong shape and contained many starch grains in DR and GSR. Higher concentrations of NO, H(2)O(2) and lipid peroxidation, higher ratio of carotenoids/chlorophyll and higher activities in T-AOC and SOD were found in DR and GSR. Na(+)/K(+)-ATPase and Ca(2+)/Mg(2+)-ATPase activities were greatest in GSR. All these data suggested that the greater relative stress tolerance of DR and GSR was due to a combination of morpho-anatomical adaptational characteristics and physio-chemical responses, and indicated the different mechanisms in their respective natural habitats.

Molecular characterization of RsMPK2, a C1 subgroup mitogen-activated protein kinase in the desert plant Reaumuria soongorica.

Reaumuria soongorica (Pall.) Maxim. is a short woody shrub widely found in semi-arid areas of China, and can survive severe environmental stresses. To understand its potential signaling transduction pathway in stress tolerance, we investigated the participation of mitogen-activated protein kinases (MAPKs) as possible mediators of abiotic stresses. A novel MAP kinase cDNA (RsMPK2) that encodes a 374 amino acid protein was isolated from R. soongorica. RsMPK2 belongs to the C1 subgroup, which is still functionally uncharacterized compared to groups A and B; and contains all 11 of the conserved MAPK subdomains and the TEY phosphorylation motif. RsMPK2 is expressed in vegetative (root, stem, leaf and callus) and reproductive (flower) organs. The transcripts of RsMPK2 were rapidly accumulated at high levels when R. soongorica was subjected to dehydration, salinity conditions and treatment with abscisic acid or hydrogen peroxide. Growth analysis of Escherichia coli (srl::Tn10) cells transformed with pPROEXHT-RsMPK2 showed that the expression products of RsMPK2 do not act as an osmoprotectant. But, the inhibition of RsMPK2 expression by the inhibitor U0126 induced a decrease of antioxidant enzyme activity under stresses, indicating that RsMPK2 is involved in the regulation of the antioxidant defense system in the response to stress signaling.

[Physiological effects of air temperature and sink-source volume at milk-filling stage of rice on its grain quality].

This paper studied the grain quality and Q-enzyme activity of three rice varieties and their combinations as affected by air temperature and sink-source volume. The results showed that at the early stage of milk filling, the grains of fully milk filling under high temperature had a higher chalkiness, lower transparency, and lower rate of white rice. Compared with the grain of early-rice, that of late rice had higher gel consistency and transparency, and higher rate of white rice. Planting rice at early-or late season had no significant effect on the amylose and protein contents of rice grain. Leaf-cutting to limit source decreased grain quality markedly, while grain-thinning to decrease sink improved grain quality significantly.